Dated : _______________
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 1
Dated : _______________
Name:_________________________________________ Class: _____________ Section:___________________ Roll No: ____________ Group:___________________
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 2
Dated : _______________ S. No
1 2
3 4 5 6 7 8 9
10
11 12 13 14 15 16
P. No
Date
To determine the value of g [ acceleration due to gravity ] by using a Kater’s pendulum. To determine the value of g [ acceleration due to gravity ] by using a compound pendulum. To determine the modulus of rigidity of the material of a given rod by static method. To determine the modulus of rigidity of the material of a given wire by dynamic method. To determine the Young’s modulus of the material of a given wire by dynamic method. To determine the coefficient of viscosity of a liquid by Stoke’s method. To determine the distance between two points by using a sextant. To determine the frequency of A.C supply by Meld’s method using a Vibrograph. To prove that the photo current is directly proportional to the intensity of light falling on photocell photo cell. or Too verify the inverse square law by using a To determine the mechanical equivalent of heat [ Value of J ] by Calander and Barne’s method. To determine the temperature coefficient of resistance of the given wire. To determine the thermal conductivity of non conductor by Lee’s method. To determine the wavelength of sodium light [ D – lines ] by diffraction grating To determine the wavelength of sodium light by Newton’s ring. To determine the surface tension of liquid by Jeager’s method. To determine the surface tension of liquid [ water ] by capillary rise method. ASIFJAH ZEHRAVI
Initial
01 05
09 13 17 22 27 30
33
39
43 49 53 56 59 62
CELL 0300 – 2568922 & 0341 – 6623062 3
Dated : _______________
LIST OF EXPERIMENTS PRACTICAL [ I ] To determine the value of g [ acceleration due to gravity ] by using a compound pendulum. To determine the value of g [ acceleration due to gravity ] by using a Kater’s pendulum. To determine the modulus of rigidity of the material of a given rod by static method. To determine the Young’s modulus of the material of a given bar by bending of beam method. To determine the Young’s modulus of the material of a given wire by dynamic method. To determine the coefficient of viscosity of a liquid by Stoke’s method.
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 4
Dated : _______________
LIST OF EXPERIMENTS PRACTICAL [ II ] To determine the distance between two points by using a sextant. To determine the frequency of A.C supply by Meld’s method using a Vibrograph. To prove that the photo current is directly proportional to the intensity of light falling on photocell photo cell. Or To verify the inverse square law by using a photo cell. To determine the mechanical equivalent of heat [ Value of J ] by Calander and Barne’s method. To determine the temperature coefficient of resistance of the given wire. To determine the thermal conductivity of non conductor by Lee’s method. To determine the wavelength of sodium light [ D – lines ] by diffraction grating To determine the wavelength of sodium light by Newton’s ring. To determine the surface tension of liquid by Jeager’s method. To determine the surface tension of liquid [ water ] by capillary rise method ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 5
Dated : _______________
EXPERIMENT NO . 1 OBJECT: To determine the value of g [acceleration due to gravity ] by using a Kater’s pendulum. APPARATUS: Kater’s pendulum , Rigid support and Stop watch. WORKING FORMULA : Accelerati on due to gravity
g 4π2
1 Slope
T2 L
Slope
Where g is the acceleration due to gravity [ g = 980 cm / sec 2 ] is the ratio of the circumference of a circle to its diameter [ It is a mathematical constant whose value is 3.142 ] T is the time period [ Time taken to complete one oscillation ] L is the effective Length of the pendulum. OBSERVATIONS: Least count of stop watch = _______________ sec Metallic End L
( cms )
Time for 10 oscillations ( Sec )
1
2
3
Wooden End
Mean time
Time period
tM
t M / 10
(Sec)
TM
Time for 10 oscillations ( Sec )
1
2
3
Mean time
Time period
tW
t W / 10
(Sec)
TW
80 75 70 65 60 ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 6
Dated : _______________ 55 50 45 CALC ULATIONS: g 4π2
Slope
1 Slope
T L
Actual Value [ Acceleration due to gravity ] 2 “ g “ 980 cm / sec
Percentage Of Error
Actual Value Calculated Value 100 Actual Value
RESULT: The value of g [ acceleration due to gravity ] using a Kater’s pendulum is calculated to be __________ cm / sec 2. Percentage of error = ______ % ___________________________
Teacher’s signature PRECAUTION: Least count of slope watch should be noted and graduation on stopwatch should be studied carefully before starting the experiment. The support should be rigid. Least count of stopwatch should be small. The amplitude of vibration should be small (not exceeding 1/10 th the length of pendulum). First four of five oscillations should not be counted as motion is non linear. The time for oscillation must be noted carefully. SOURCES OF ERROR : ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 7
Dated : _______________
Non-linearity of the meter scale. The support of pendulum is not rigid. Inaccuracy of stopwatch. Presence of air draughts.
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 8
Dated : _______________
EXPERIMENT NO . 2 OBJECT: To determine the value of g [acceleration due to gravity ] by using a Compound pendulum. APPARATUS: Stop watch ,
Compound or Bar pendulum , Rigid support ,
WORKING FORMULA : L T2
g 4π2
Where g is the acceleration due to gravity [ g = 980 cm / sec 2 ] is the ratio of the circumference of a circle to its diameter [ It is a mathematical constant whose value is 3.142 ] T is the time period [ Time taken to complete one oscillation ] L is the effective Length of the pendulum. OBSERVATIONS: Least count of stop watch = _______________ sec Distance from support to C.G.
End
A ]
End
B ]
Time for 10 oscillations ( Sec )
Mean t
Time period t / 10
1
(Sec)
1
(Sec)
( Sec )
2
3
Mean
[
Time Time period t / 10 t
L ( cms )
[
Time for 10 oscillations ( Sec )
(Sec)
2
3
time
45 40 35 30 25 20 15 10 ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 9
Dated : _______________ CALCULATIONS:
Computed Length L
KM LN 2
g 4π2
L T2
Actual Value [ Acceleration due to gravity ] 2 “ g “ 980 cm / sec
Percentage Of Error
Actual Value Calculated Value 100 Actual Value
RESULT: The value of g [ acceleration due to gravity ] using a compound pendulum is calculated to be _______cm / sec 2. Percentage of error = ___________________ % ___________________________
Teacher’s signature
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 10
Dated : _______________ PRECAUTION: Least count of slope watch should be noted and graduation on stopwatch should be studied carefully before starting the experiment. The support should be rigid. Least count of stopwatch should be small. The amplitude of vibration should be small (not exceeding 1/10 th the length of pendulum). First four of five oscillations should not be counted as motion is non linear. The edges K1 and K2 must be sharp. SOURCES OF ERROR :
Non-linearity of the meter scale. The support of pendulum is not rigid. Inaccuracy of stopwatch. Presence of air draughts.
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 11
Dated : _______________
EXPERIMENT NO . 3 OBJECT: To determine the modulus of rigidity of the material of a given rod by static method. APPARATUS: Torsion apparatus , Slotted weights with hanger , Thread , Meter scale and Screw gauge.
WORKING FORMULA : η
360 M g L R π2 r4 [ θ θ ] 2 1
C = 2 R Where is the mmodulus of rigidity of the material of a given rod M is the mass suspended g is the acceleration due to gravity [ g = 980 cm / sec 2 ] L is the length of the rod between the two pointers C is the circumference of the pulley. ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 12
Dated : _______________ R is the radius of the pulley. is the ratio of the circumference of a circle to its diameter [ It is a mathematical constant whose value is 3.142 ] r is the radius of the rod. is the angle of twist produced at pointer No . 1 is the angle of twist produced at pointer No . 2 OBSERVATIONS: 1. Least count of screw gauge LC = 0.0 1 mm = 0. 001 cm. 2. Circumference of the pulley 3. Radius of the pulley
C
=
____________ cm.
R = ____________________cm.
4. Length of the rod between the two pointers = L 5. = _______________ cm. TABLE FOR RADIUS OF THE METALLIC ROD S NO
MSR
mm
CSR
FP = CSR LC
Diameter MSR + FP
Mean Diameter
mm
mm
mm
div
Radius Radius
r
r
mm
cm
1. 2. 3.
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 13
Dated : _______________ TABLE FOR ANGLE OF TWIST S NO
POINTER READING
Mass Suspended
grams
Load
Decreasing
Deg
Deg
1.
500
2.
1000
3.
1500
1.
2000
2.
2500
3.
3000
2
Mean
1
2
deg
deg
Load
Increasing
1
M
Mean
1
[ 2 – 1] degrees
2
Twist for 500 gms deg
CALCULATIONS: η
360 M g L R π2 r4 [ θ θ ] 2 1
C = 2 R Actual Value [ Modulus of rigidity of copper rod ] ““
4.55 10 11 Dynes / cm 2
Percentage Of Error
Actual Value Calculated Value 100 Actual Value
RESULT: The modulus of rigidity of the material of a given rod is calculated to be________________________ dynes / cm 2 ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 14
Dated : _______________ Percentage of error = ___________________ %
Teacher’s signature PRECAUTION: Radius of the rod must be measured accurately. Pointer must be free to rotate over the scale. Twisting of the rod should be uniform through out the length. After changing the suspended weight , wait for a while. SOURCES OF ERROR :
Non-linearity of the meter scale. In accurate measurement of the radius of the rod. Pointers may not be free to rotate on the scale. Non uniform twisting of the rod.
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 15
Dated : _______________
EXPERIMENT NO . 4 OBJECT: To determine the modulus of rigidity of the material of a given rod by dynamic method. APPARATUS: A hollow tube , Two hollow cylinders and Two solid cylinders of equal length and equal diameter , Long wire , Lamp with Scale arrangement , Stop watch , Screw gauge , Meter scale and Physical balance. WORKING FORMULA : η
8 π l2 L [ m m ] 2 1 4 2 2 r [ T T ] 2 1
Where is the modulus of rigidity of the material of a given wire is the ratio of the circumference of a circle to its diameter [ It is a mathematical constant whose value is 3.142 ] l is the half length of the hollow tube. L is the length of the wire m is the average mass of the hollow cylinders. m 2 is the average mass of the solid cylinders. T is the time period for 10 oscillations when the solid cylinders are at the inner position T 2 is the time period for 10 oscillations when the hollow cylinders are at the inner position r is the radius of the wire. OBSERVATIONS: 1. Least count of screw gauge LC = 0 . 0 1 m m = 0. 001 c m. 2. Total length of the hollow tube = 2 l = _____________ cms. 3. Half length of the tube = 2 l = __________________ cms. 4. Length of the wire = L = ______________________ cms. ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 16
Dated : _______________ 5. Total mass of the hollow cylinders = m T = ________ gms. 6. Average mass of the hollow cylinders m = m T /2 =___gms. 7. Total mass of the solid cylinders = m gms 8. Total mass of the solid cylinders =____gms.
m
= _________
t
2
= m
t
/ 2
9. Radius of the wire r S NO
MSR
CSR
mm
FP = CSR LC
Diameter MSR + FP
Mean Diameter
mm
mm
mm
div
Radius Radius
r
r
mm
cm
1. 2. 3. S NO
Time period for 10 oscillations when the solid cylinders are at the inner position T Sec 1
2
3
Time period Mean T = t / 10 T Sec Sec
Mean
1. 2. 3.
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 17
Dated : _______________ S NO
Time period for 10 oscillations when the hollow cylinders are at the inner position T Sec 1
2
3
Time period Mean T 2 = t / 10 T 2 Sec Sec
Mean
1. 2. 3.
8 π l2 L [ m m ] CALCULATIONS: 2 1 η 4 2 2 r [ T T ] 2 1 Actual Value [ Modulus of rigidity of copper rod ]
““
4.55 10 11 Dynes / cm 2
Percentage Of Error
Actual Value Calculated Value 100 Actual Value
RESULT: The modulus of rigidity of the material of a given wire is calculated to be________________________ dynes / cm 2 Percentage of error = ___________________ %
___________________________
Teacher’s signature PRECAUTION: Radius of the wire must be measured accurately. The support should be rigid ie the support of the pendulum should not vibrate along with the pendulum. Vibration of the tube must be in one plane. ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 18
Dated : _______________ Area of the wire should be uniform through out the length. Surface of the Maxwell’s tube must be small. Amplitude of vibration must be small. There should be no kinks in the wire. SOURCES OF ERROR :
Non-linearity of the meter scale. In accurate measurement of the radius of the rod. Kinks in the wire. Non rigid support. Non uniformity of the radius of wire. Air drag.
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 19
Dated : _______________
EXPERIMENT NO . 5 OBJECT: To determine the Young’s modulus of the material of a given bar by bending of beam method. APPARATUS: Given metallic bar , Meter Scale , Spherometer , Slotted weights , Vernier calipers , Cell and Connecting wire.
WORKING FORMULA :
Y
M g L3 4 y b d3
Where Y is the Young’s modulus of the material of a given bar. M is the mass suspended g is the acceleration due to gravity [ g = 980 cm / sec 2 ] L is the length of the bar between the two knife edges. y is the depression produced in the bar b is the breadth of the bar. d is the thickness of the bar. OBSERVATIONS: Least count of screw gauge LC ms . S NO
MSR
CSR
mm
div
= 0 . 0 1 m . m = 0. 001 c
FP = CSR Thickness Mean MSR + FP Thickness LC mm mm mm
1. 2. 3. ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 20
Dated : _______________ Least count of vernier calliper’s LC = 0 . 1 m . m = 0. 01 cm S NO
MSR
VSR
mm
div
FP = VSR LC mm
Breadth MSR + FP mm
Mean Breadth mm
1. 2. 3. S NO
Mass Load Sus Increasing pended MSR CSR FP TR M cms
div
cms
cms
Load Decreasing MSR cms
CSR cms
FP cms
A grams
1.
50
2.
100
4.
150
5.
200
6.
250
7.
300
8.
Mean Reading y TR Cms
B
[ A B ] 2
Twist Mean for Twist 500 for gms 500 y gms y
cms
cms
cms
350 CALCULATIONS: Y
M g L3 4 y b d3
Actual Value [ Young’s modulus of iron ] 11 Dynes / cm 2 “ “ [ 19 – 20 ] 10 [ Young’s modulus of steel ] 11 Dynes / cm 2 “ “ [ 19.5 – 20.6 ] 10 ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 21
Dated : _______________ Percentage Of Error
Actual Value Calculated Value 100 Actual Value
RESULT: The Young’s modulus of the material of a given bar by bending of beam method .is calculated to be___ dynes / cm 2 Percentage of error = ___________________ % ___________________________
Teacher’s signature PRECAUTIONS: Edges on which the bar is suspended must be sharp and rigid and must be perpendicular to the length of the bar. Load must be changed in regular steps. Load must be suspended at the centre of gravity of the bar and it’s distance must be equal from the two knife edges. The bar must be of uniform thickness. Thickness of the bar must be measured accurately. Positions of the sharp edges must be kept fixed through out the experiment. SOURCES OF ERROR: Edges may not be sharp. In accurate measurement of the Breadth and thickness of the bar. The sharp edges may not be fixed during the experiment. Load may not be changed in a regular steps.
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 22
Dated : _______________
EXPERIMENT NO . 6 OBJECT: To determine the coefficient of viscosity by Stoke’s method. APPARATUS: Given liquid , Small ball bearings , Stop watch , Screw gauge , Vernier calipers , Long glass tube fitted to a wooden frame , Meter scale WORKING FORMULA:
V V [ 1 0
2. 4 r R
]
2 π r 2g [ d - D ] η 9 V 0 Where
is the coefficient of viscosity. is the ratio of the circumference of a circle to its diameter [ It is a mathematical constant whose value is 3.142 ] r is the radius of the spherical body
g is the acceleration due to gravity
[ g = 980 cm / sec 2
] d is the density of the ball bearing. D is the density of the liquid.
V0 is the terminal velocity. X is the inner diameter of the glass tube. R is the inner radius of the glass tube. V is the observed Velocity
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 23
Dated : _______________ OBSERVATIONS: 3
Density of the ball bearing. = d = 7. 8 gm / cm
Density of the given liquid = D = 1. 26 gm / cm Smallest division division on main scale _____cm.
3
=
a
=
Total number of divisions on vernier scale _____cm.
=
b
=
Least
=
a b
=
count
or
Vernier
constant
____________cm. Inner diameter of the glass tube = X = 3 . 5 cm Inner radius of glass tube = R = r = d / 2 = 3.5 / 2 = 1. 75 cm Pitch of the screw =
Distance moved on main scale =_____m. Number of rotation
m
Total
number of =_______divisions
Least count =
on
circular
scale
Pitch of the screw Total number of divisions on circular scale
Least count =_____________cm. Zero error Z =_____________cm.
ASIFJAH ZEHRAVI
divisions
=______________m
=______________m
.
m
.
m
CELL 0300 – 2568922 & 0341 – 6623062 24
Dated : _______________ FOR DIAMETER OF BALL BEARING Size of balls
M.S.R
C.S.R
Fractional Part
Diameter
Corrected Diameter
D = FP + MSR
D T [ Z]
FP = CSR LC
mm
mm
mm
div
mm
Large Medium Small
FOR TERMINAL VELOCITY Size of Distance Ball Covered bearings S
Time taken to cover distance S 1
2
3
Mean
Observed Velocity V
Terminal velocity V0 =
S t
V (1
2. 4 r R
cm Large
60
Medium
60
Small
60
sec sec sec
sec
cm / sec
V V [ 1 0
CALCULATIONS:
2. 4 r R
cm / sec
]
2 π r 2g [ d - D ] η 9 V 0 Actual Value [ Coefficient of viscosity of glycerin ] “ “ [ 8.39 ] Poise at 20 C Percentage Of Error
ASIFJAH ZEHRAVI
Actual Value Calculated Value 100 Actual Value
CELL 0300 – 2568922 & 0341 – 6623062 25
)
Dated : _______________ RESULT: The thermal conductivity of non conductor by Lee’s method is calculated to be ______________ cal / sec / cm / C Percentage of error = ___________________ %
___________________________
Teacher’s signature
PRECAUTION: Least count of stop watch should be noted and graduation on stopwatch should be studied carefully before starting the experiment. The ball bearings must be released slowly from just above the liquid surface. Temperature of the liquid should remain constant through out the experiment. Ball bearings must be released in the middle of the tube. Liquid should be transparent and free of dust particles. Surface of the ball bearings must be free of dust and grease. Tube must be vertical. SOURCES OF ERROR : Inaccuracy of stopwatch. Liquid may not be pure. Change of temperature during the experiment. Surface of the balls may not be free of grease The tube may not be exactly vertical
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 26
Dated : _______________
EXPERIMENT NO . 7 OBJECT: To determine the surface tension of liquid by Jeager’s method. APPARATUS: Complete Jeager’s apparatus, Given liquid contained in a beaker , Traveling microscope.
WORKING FORMULA: surface tension of the given liquid by Jeager’s method is given by
T
rg [ HD - d ( h 2
2r 3
) ]
Where r is the radius of the jet bore. g is the acceleration due to gravity [ g = 980 cm / sec 2 ] H is the difference of height between the liquid levels in the two limbs of manometer. D is the density of the manometer liquid. d is the density of the experimental liquid ( water ) contained in the beaker. h is the length of the jet tube dipped in to the experimental liquid.
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 27
Dated : _______________ OBSERVATIONS: Least count of ___________cm S NO
traveling
Traveling microscope readings when origin of it’s cross wires are focused on Right edge Left edge
[X]
[y]
cm
cm
microscope
Diameter of the jet
=
LC
=
D =Y–X
Mean Diameter of the jet
Radius of the jet
cm
cm
cm
1. 2. 3.
OBSERVATIONS: Density of the manometer liquid [ water ] = D = 1 gm / cm 3 Density of the experimental liquid [ water ] = d = 1 gm / cm 3 Acceleration due to gravity = g = 980 cm / sec 2 Room temperature = T = ____________________ C S NO
Length of the jet tube dipped in the liquid
h cm
Position of liquid column just before the detachment of an air bubble in the Closed limb Open limb
Difference of height between the two liquid levels
[A]
[B]
H =B–A
cm
cm
cm
1. 2. 3. ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 28
Dated : _______________ CALCULATIONS:
T
rg [ HD - d ( h 2
2r 3
) ]
Actual Value [ Surface tension of water ] “T“ Percentage Of Error
73 dynes / cm
Actual Value Calculated Value 100 Actual Value
RESULT: The surface tension of liquid by Jeager’s method.is calculated to be ____________________ dynes / cm. Percentage of error = ___________________ %
___________________________
Teacher’s signature
PRECAUTION: The jet tube must be circular and should be of very small diameter so that the bubbles formed are spherical in shape. Length of the jet tube dipped in the experimental liquid must be measured accurately. Apparatus must be air tight. The experimental liquid should be free from dust. The experimental liquid must be pure. For accurate measurement of liquid levels in manometer the rate of formation of bubbles must be slow SOURCES OF ERROR : Experimental liquid may not be pure. Temperature of the liquid may not be constant. Jet may not be perfectly circular.
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 29
Dated : _______________
EXPERIMENT NO . 8 OBJECT: To determine the surface tension of liquid [ water ] by capillary rise method. APPARATUS: Capillary tubes of uniform bore and different diameters, Thin rubber tube band, Sharp pointed needle, Clamping stand, Thermometer , Given liquid, Traveling microscope and An adjustable stand.
WORKING FORMULA: surface tension of the given liquid by capillary rise method is given by
T
hr ρg 2
Where T is the surface tension of the given liquid. h is the height of the liquid column. r is the radius of the tube used. d is the density of the experimental liquid ( water ) used. g is the acceleration due to gravity [ g = 980 cm / sec 2 ]
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 30
Dated : _______________ OBSERVATIONS: [ FOR GIAMETER OF THE TUBE ] Least count of ___________cm S NO
traveling
Traveling microscope readings when it’s cross wires are focused on Right Left Upper Lower edge edge edge edge
[A] cm
[B] cm
[C] cm
[D] cm
microscope
Diameter of the tube D =B–A
=
LC
Diameter of the tube D=B–A
=
Mean Diameter of the tube
D cm
cm
cm
1. 2. 3.
Radius of the tube = r = D / 2 ___________cm OBSERVATIONS: [ FOR HEIGHT OF THE LIQUID COLUMN ] Temperature of water = T = ____________________ C Density of the liquid [ water ] = = 1 gm / cm 3 Tube No
Microscope reading at Lower meniscus
Lower tip of the needle
[A] cm
[B] cm
Difference of height
Radius of tube
h = A–B
r
cm
cm
T
hr ρg 2
dynes /cm
1. 2. 3.
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 31
Dated : _______________ CALCULATIONS:
T
hr ρg 2
Actual Value [ Surface tension of water ] “T“ Percentage Of Error
73 dynes / cm
Actual Value Calculated Value 100 Actual Value
RESULT: The surface tension of liquid [ water ] by capillary rise
method is calculated to be ________________ dynes / cm. Percentage of error = ___________________ %
___________________________
Teacher’s signature
PRECAUTION: The capillary tube should be of fine and uniform bore. The tube should be vertical and sufficiently apart. As for as possible use of wax for fixing the tubes should be avoided In stead of use of a thin rubber band be preferred. The container should be full with the water level slightly above it’s edges. The water surface should be free from grease and hence should never be touched with fingers. The lower tip of the needle should be just above the water surface and not dip in to it. The tube should be cut and it’s diameter determined at the level of water meniscus. ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 32
Dated : _______________ The diameter of the tubes should be measured in two cross wire positions. Use of distilled water should be avoided. The experimental liquid should be free from dust. The experimental liquid must be pure. SOURCES OF ERROR :
Non uniform capillary tube may be used. Capillary tube may not be exactly vertical. Surface of water may be greasy. Diameter of the capillary tube may not be measured accurately. Experimental liquid may not be pure. Temperature of the liquid may not be constant.
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 33
Dated : _______________
EXPERIMENT NO . 9 OBJECT: To determine the distance between two points by using a sextant. APPARATUS: Sextant , Meter scale and Vertical stand.
WORKING FORMULA :
d
L Cot α - Cot β
OR d
L [ Tan α Tan β ] Tan β - Tan α
Where d is the distance between the two points on the wall. L is the distance through which Sextant is moved. is the angle through which the index arm is turned to coincide the images of two the points. is the angle through which the index arm is turned after moving the Sextant distance L to coincide the images of two the points. .
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 34
Dated : _______________ OBSERVATIONS: Least count of the Sextant = _______________ sec
S NO
L1
cm
When AA are in St. line
Angle B When AB are in St. line
[B – A]
deg
deg
degrees
Angle A
Angle
=
L2
cm
1.
0
50
2.
50
100
3. 100
150
Angle Angle C D When AA are in St. line
When AB are in St. line
cm
cm
Angle
Distance
=
L= [D – C] [L2 – L1]
degrees
CALCULATIONS:
d
L Cot α - Cot β
OR d L [ Tan α Tan β ] Tan β - Tan α
Actual Value [ Acceleration due to gravity ] “d“ Percentage Of Error
96 cm
Actual Value Calculated Value 100 Actual Value
RESULT: The distance between the two points A and B by using the sextant is calculated to be _________________ cm. Percentage of error = ___________________ %
___________________________
Teacher’s signature ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 35
cm
Dated : _______________ PRECAUTION: Least count of the sextant should be determined accurately The points A and B should be in a plane perpendicular to the line joining the lower point A with the sextant. The lower point A must be at the level of the sextant. Sextant should be firmly fixed to the stand. The sextant should be properly leveled. Parallax between directed and reflected images should be removed completely. The sextant should be clamped in vertical position, so that axis of the telescope is horizontal. The telescope should be in level with the lower mark. The two images should overlap and should have equal intensity. Rotate the moveable arm slowly SOURCES OF ERROR : Parallax between direct and reflected images may not have been removed completely. In accurate reading of the instruments. Mirrors of the sextant may not be parallel to each other
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 36
Dated : _______________
EXPERIMENT NO . 10 OBJECT: To determine the frequency of A.C supply by Meld’s method using a Vibrograph. APPARATUS: A.C. main supply , Vibrograph with step down voltage transformer , String , Pan , Adjustable pulley , Two upright pins , Weights and meter scale.
WORKING FORMULA : Frequency of string F s
Frequency of A . C main supply
1 2L 1 2L
M g μ M g μ
Mean F s 2
Where
FS is the frequency of string. L is the distance between two consecutive nodes. [ Length of single loop ] M is the total mass suspended. g is the acceleration due to gravity [ g = 980 cm / sec 2 ] is the linear density of the string.
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 37
Dated : _______________ OBSERVATIONS: Mass of pan suspended m1 = ______________ gm. Mass per unit length of the string ( Linear density ) =_____ gm / cm. S. NO
Mass placed in pan m2 gm
Total mass M = m
1
+ m2
Number Of Loops
N gm
Length of N loops L cm
Length of One loops L = l / N cm
1. 2. 3. 4. 5.
CALCULATIONS: M g μ
F s
1 2L
F a. c
Mean F s 2
[ For each observation ]
Actual Value [ Frequency of A.C. main ] “ A.C Main ” Percentage Of Error
50 Hertz or cycles / sec
Actual Value Calculated Value 100 Actual Value
RESULT: The frequency of A.C supply by Meld’s method using a Vibrograph is calculated to be ________________ Hertz Percentage of error = ___________________ % ___________________________
Teacher’s signature ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 38
Dated : _______________ PRECAUTION: The string should be of uniform area of cross-section. It should have no knots. The string should be stretched horizontally. The string, the vibrator or and the pulley should be in the same straight line. Pan should be suspended freely and must be stationary when readings are taken. The weights should be gently transferred to or from the pan. The wave, set up should be well defined, stationary and of large amplitude. Pulley should be well oiled to reduce friction. While taking the length of N loops the end loops must be omitted as initial and final node is not clear. Pins should be placed at exact position of nodes. The string should have no knots. SOURCES OF ERROR :
Non uniformity of linear density of string. Friction at pulley. Large least count of weights. Given linear density and weight. Personal error in measuring the length.
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 39
Dated : _______________
EXPERIMENT NO . 11 OBJECT: To prove that the photo current is directly proportional to the intensity of light falling on photocell photo cell. or Too verify the inverse square law by using a APPARATUS: Photo voltaic cell, Micro ammeter , Electric lamp , Meter scale , A – C Main supply and connecting wires. WORKING FORMULA: For inverse square law of radiation Intensity of light E
1 d2
From the experiment Photo electric current I Hence Intensity of light E E
1 d2
Photo electric current I I
Where d is the distance between the source of light and photocell CIRCUIT DIAGRAM:
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 40
Dated : _______________ OBSERVATIONS: Least count of Micro ammeter = 5 Ampere S. NO.
Micrometer Reading
d
d
2
2
cm
cm
1.
100
2.
90
3.
80
4.
70
5.
60
6.
50
7.
40
8.
30
1 d2
Inc
cm–2
A
With 40 W
With 60 W
bulb
bulb
Dec Mean Inc Dec Mean
I1 A
A
I2 A
A
A
I 1d 2 I 2d 2 2
A cm
CALCULATIONS: 1 d2
[ For each observations ]
I 1 d 2 [ For each observations ] I 2 d 2 [ For each observations ]
ASIFJAH ZEHRAVI
2
A cm
CELL 0300 – 2568922 & 0341 – 6623062 41
Dated : _______________ RESULT: The graph between current I and
1 is a straight line which confirm d2
that the photoelectric current is directly proportional to the intensity of light The values of
I 1 d 2 and I 2 d 2 are constant for each bulb.
The value of
I 1 is found to be _______ I 2 ___________________________
Teacher’s signature PRECAUTION: Connections must be tight and free from insulating material at the end. The height of lamp and height of photocell should be same. Distance should be measured carefully. Zero error of micro ammeter should be noted. Least count of micro ammeter should be noted. Window of photocell should be opened after the lamp is switched on. Personal movement should minimum so that light is not blocked. SOURCES OF ERROR:
Large least count of micro ammeter. Height of lamp or photocell may not be same. Presence of light in the surroundings. Change in the illumination of light in the surrounding.
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 42
Dated : _______________
EXPERIMENT NO . 12 OBJECT: To determine the mechanical equivalent of heat [ Value of J ] by Calander and Barne’s method. APPARATUS: Callender and Barne’s apparatus , Constant pressure head device Ammeter , Voltmeter , Rheostat , Two Thermometer , Accumulator , Physical balance , Stop watch and Connecting wires. WORKING FORMULA:
J
V I t m C ( T T ) F I
Where
V is the the voltage applied across the resistor. I is the current passed through the resistor for t sec. t is the time for which the mass of water is collected. m c is the mass of water collected. TI is the temperature of water [ At Inlet ] TF is the temperature of water. [ At Outlet ]
CIRCUIT DIAGRAM:
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 43
Dated : _______________ OBSERVATIONS: 1. Least count of voltmeter
= ___________________________ Volts
2. Least count of Ammeter
= ___________________________ Amps
3. Least count of thermometer
= ________________________ C
4. Mass of empty beaker = m b = _______________________ gm. 5. Mass of beaker + water = M = ______________________ gm. 6. Mass of water collected = m = 7. Specific heat of water
[
M–m b
]
___________ gm.
= S b = 1 Cal / gms °C
8. The voltage applied across the resistor = V = __________ Volts 9. Current passed through the resistor
= I = ___________ Amp
10. Time for which the current is passed = t = ________________ min 11. Initial Temperature of water [ At Inlet ] = TI
= _______°C
12. Final temperature of water [ At Outlet ] = TF
= ________°C
S. NO
Time ( t )
Voltage (V)
Current (I)
minutes
Volts
Amp
Temperature Temperature At Inlet At Outlet ( T 1 ) °C ( T 2 ) °C °C
°C
1. 2. 3. 4. 5. 6.
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 44
Dated : _______________ CALCULATIONS: Time for which the current is passed = t = _____ min 60 = _____Sec
V I t m C ( T T ) F I Actual Value [ Value of J ( Mechanical equivalent of heat ) ] J
“J“
4.19 Joules / calorie
Percentage Of Error
Actual Value Calculated Value 100 Actual Value
RESULT: The mechanical equivalent of heat [ Value of J ] by Calander and Barne’s method is calculated to be ________ J / cal. Percentage of error = ___________________ %
___________________________
Teacher’s signature PRECAUTION: There should be no air bubbles in the tube. Turns of the resistor wire may not touch each other or side of the tube. Current must be switched on after maintaining a steady flow of water through the tube. The tube must be air tight so that there should be no leakage of water SOURCES OF ERROR : Inaccuracy of stopwatch. There may be air bubbles in the tube. The most important source of error is the loss of heat due to radiation. ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 45
Dated : _______________
EXPERIMENT NO . 13 OBJECT: To determine the temperature coefficient of resistance of the given wire. APPARATUS: Meter bridge, Galvanometer, Resistance box, Cell, Thermometer , Given coil , One way key and Connecting wires. THEORY: The resistance of a pure metal wire changes with temperature according to the relation R t = R0 [ 1 + t + t 2 ] Where and are constants R t and R0 are the resistances of the metal at temperatures of t C and 0 C respectively . The constant is very small compared with and for moderate temperature range the above relation can be written as R t = R0 [ 1 + t ] The constant is known as temperature coefficient of resistance. If R t and R0 are the resistances of a metal at t C and 0 C are known the value of can be computed by the relation
R
t R
- R 0
0 t
R
- R t 0 R [ t t ] 1 0 2
However the measurement of resistance R0 at 0can be avoided. If R1 and R2 are the resistances of the metal wire at t1 ( say room temperature ) and t2 ( say boiling point of water ) are measured , then the value of can be determined by the relation.
α ASIFJAH ZEHRAVI
R
- R 1 [ R t R t ] 1 2 2 1 2
CELL 0300 – 2568922 & 0341 – 6623062 46
Dated : _______________ WORKING FORMULA:
R
- R t 0 R [ t t ] 1 0 2
,
α
R
- R 1 [ R t R t ] 1 2 2 1 2
Where is the temperature coefficient of resistance of the given wire. R t is the resistances of the metal wire at t C R0 is the resistances of the metal wire at 0 C R1 is the resistance of the metal wire at t1 ( say room temperature ) R2 is the resistance of the metal wire at t2 (say boiling point of water ) T1 is the room temperature T2 is the boiling point of water CIRCUIT DIAGRAM:
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 47
Dated : _______________ OBSERVATIONS: Least count of thermometer = ________________________ °C S. NO
Temperature At Inlet T
Known Resistance R
°C Room temp
Ohm
LX
LR
X R
L L
cm
cm
X
R
Ohm
1. 2.
100
3.
90
4.
80
5.
70
6.
60
7.
50
CALCULATIONS:
α
R
- R t 0 R [ t t ] 1 0 2 R
- R 1 [ R t R t ] 1 2 2 1 2
Actual Value [ Temperature coefficient of resistance for Nichrome wire ] “ “ 0.00017 Per degree centigrade [ Temperature coefficient of resistance for Manganin wire ] “ “ 0.00001 Per degree centigrade Percentage Of Error
ASIFJAH ZEHRAVI
Actual Value Calculated Value 100 Actual Value
CELL 0300 – 2568922 & 0341 – 6623062 48
Dated : _______________ RESULT: The temperature coefficient of resistance of the given wire is calculated to be ______________ per degree centigrade. Percentage of error = ___________________ %
___________________________
Teacher’s signature PRECAUTION:
All connections should be neat and tight. Short and thick connecting wires should be used. The jockey must have sharp edge. Avoid the sliding of jockey on the wire rather it should be gently tapped over it. The plugs of resistance box should be tight in their gaps. Care should be taken in handling the apparatus. SOURCES OF ERROR : Loose connections Error due to the sliding of jockey on the wire. Use of long and thin connecting wires may add more resistance in the circuit. Loose plugs in the resistance box . Jockey may not be of sharp edge . Fluctuation of current in the circuit.
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 49
Dated : _______________
EXPERIMENT NO . 14 OBJECT: To determine the thermal conductivity of non conductor by Lee’s method. APPARATUS: Lee’s thermal conductivity apparatus , Given circular shaped non conductor , Steam generator , Vernier calipers , Screw gauge , Stop watch , Two sensitive thermometer.
WORKING FORMULA:
K
ML C dT A [ T T ] dt 2 1
Where
K is the thermal conductivity of non conductor. M is the mass of metal slab L is the thickness of non conductor [ Card board ] C is the specific heat of metal A is the cross sectional area of non conductor.
dT is the rate of cooling of the metal slab at Steady state dt
T1 is the steady state temperature of metal slab T2 is the temperature of steam chamber. temperature
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 50
Dated : _______________ OBSERVATIONS: 1. Mass of metal slab = M = ___________________________ grams. 2. Specific heat of metal = C =____________________cal / grams C 3. Steady state temperature of metal slab =
T1
= ______________ C
4. Steady state temperature of steam chamber =
T2
= __________ C
5. Thickness of non conductor [ Card board ] = L =__________ cm 6. Diameter of non conductor [ Card board ] = d =___________ cm 7. Radius of non conductor [ Card board ] = r = d / 2 =_______ cm 8. Cross sectional area of non conductor.
S. NO
Time
Temperature
t
T
sec
C
S. NO
1.
11.
2.
12.
3.
13.
4.
14.
5.
15.
6.
16.
7.
17.
8.
18.
9.
19.
10.
20.
ASIFJAH ZEHRAVI
= A=r
2
_______ cm 2
Time Temperature
t
T
sec
C
CELL 0300 – 2568922 & 0341 – 6623062 51
Dated : _______________ CALCULATIONS: From graph d T = _____________ K d t = _____________ min Rate of cooling of the metal Slab at steady state dT = ______________ dt
ML C dT A [ T T ] dt 2 1 Actual Value [ Thermal conductivity of poor conductor ] Cork board 0.00011 cal / sec / cm / C K
Percentage Of Error
Actual Value Calculated Value 100 Actual Value
RESULT: The thermal conductivity of non conductor by Lee’s method is calculated to be ______________ cal / sec / cm / C Percentage of error = ___________________ %
___________________________
Teacher’s signature PRECAUTION: Least count of stop watch should be noted and graduation on stopwatch should be studied carefully before starting the experiment. Diameter of metallic slab , card board and steam chamber must be equal. Surface of the metallic slab and card board must be smooth so that they come in good thermal contact.
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 52
Dated : _______________ SOURCES OF ERROR : Inaccuracy of stopwatch. Diameter of card board may not be equal to diameter of metallic slab and steam chamber. Loss of heat from edges of the slab and the bad conductor. Presence of condensed water in the steam chamber is an important source of error.
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 53
Dated : _______________
EXPERIMENT NO . 15 OBJECT: To determine the wavelength of sodium light [ D – lines ] by diffraction grating
APPARATUS: Spectrometer , Diffraction grating , Sodium lamp , Sprit level. WORKING FORMULA:
N = d Sin
λ
d Sin θ N
Where is the wave length of sodium light. d is the grating element. is the angle of diffraction of the sodium light. N is the order of spectrum.
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 54
Dated : _______________ OBSERVATIONS: Least count of stop watch = 1 minute. Number of lines ruled on the grating = ________lines / inch. Grating element = d S NO
Order Of Image
1inch no of lines
Lines Diffraction reading on Right Left side side [A] [B]
deg 1.
I
D1
2.
II
D2
2.54 cm [
= _______cm
]
Difference Of Readings 2 = A – B
Angle of diffraction
Wave length
deg
deg
cm
deg
λ
CALCULATIONS:
d Sin θ N
Actual Value [ Wave length of spectral lines of sodium ] o Yellow D 1 –8 5896 10 cm 5896 A o Yellow D 2 –8 5890 10 cm 5890 A Percentage Of Error
Actual Value Calculated Value 100 Actual Value
RESULT: The wavelength of sodium light [ D – lines ] by diffraction grating is calculated to be ______ 10
–8
o
cm ______ A
Percentage of error = ___________________ % ___________________________
Teacher’s signature
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 55
Dated : _______________ PRECAUTION: Do not touch or attempt to clean the surface of the grating. Spectrometer must be set properly before using it. Ruled surface of the grating must face away from the collimator. The eyepiece should be focused on the cross wire carefully. The telescope and collimator should be adjust for parallel rays. The grating should be adjusted parallel to the axis of rotation of the table. The grating should be adjusted perpendicular to the collimator with it’s ruled surface away from it. The grating lines should be parallel to the axis of rotation of the table. The silt should be made extremely narrow while taking readings. SOURCES OF ERROR : The grating surface may be touched by fingers. Spectrometer may not be set properly. Ruled surface of the grating may be facing towards the collimator. The cross wire of the telescope may not be focused carefully. The grating may not be exactly perpendicular to the collimator.
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 56
Dated : _______________
EXPERIMENT NO . 16 OBJECT: To determine the wavelength of sodium light by Newton’s ring. APPARATUS: Sodium lamp , Sprit level., Convex lens of suitable focal length ( Usually lens of long focal length is used ) Plane glass plate ,Traveling microscope. WORKING FORMULA: wavelength of sodium light by Newton’s ring can be calculated as
Dn2 Dm2 λ 4 R[n - m ] Where is the wave length of light used. th D n is the diameter of n dark ring ( Outer ring ) th D m is the diameter of m dark ring ( Inner ring R is the radius of curvature of the lens. OBSERVATIONS: Least count of traveling micrometer
= ____________cm.
Radius of curvature of lens used = R = _____________cm S NO
Ring Number
Microscope reading on Right side [A]
Left side [B]
Difference Of Readings 2 = A – B
cm
cm
cm
1. 2. 3. 4.
CALCULATIONS: wavelength of sodium light by Newton’s ring . ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 57
Dated : _______________ Dn2 Dm2 λ 4 R[n - m ] Actual Value [ wavelength of sodium light “ “ ] Yellow D 1 Yellow D 2 Percentage Of Error
5896 10
–8
5890 10
–8
cm 5896 cm 5890
o A o A
Actual Value Calculated Value 100 Actual Value
RESULT: The wavelength of sodium light by Newton’s ring is o
calculated to be ________ cm or ___________ A Percentage of error = ___________________ %
___________________________
Teacher’s signature PRECAUTION: A lens of large radius of curvature should be used. The point of interaction of crosswire should coincide with the centre of ring system. One of the crosswire should be perpendicular to the scale of microscope. The microscope should be moved in the same direction while measuring the diameter of a ring to avoid back lash error. The radius of curvature of the surface of the lens in contact with the glass plate should be measured. Lens and the glass plate should be cleaned properly so that no dust particles remains between them at the point of contact, this is necessary for making the center of rings always dark. Screw of the travelling microscope must be rotated as for as possible in one direction ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 58
Dated : _______________ The glass plate must be held at an angle of 45 to the light beam so that light must fall perpendicularly on the lens. Travelling microscope readings must be taken accurately. SOURCES OF ERROR :
Lens and glass plate may not be clean. Readings of microscope may not be accurate. Micro scope screw may have slight backlash error. The glass plate may not be held at an angle of 45 to the beam of light.
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 59
Dated : _______________
EXPERIMENT NO . 17 OBJECT: To determine the thermal conductivity of good conductor ( copper ) by Searle’s apparatus. APPARATUS: Searle’s thermal conductivity apparatus , Steam generator with heating arrangement, Vernier calipers, Stop watch , Four sensitive thermometer.
WORKING FORMULA:
K
ML C [ T - T ] 4 3 A [ T T ] 2 1
A
π r 2
Where K is the thermal conductivity of good conductor ( copper ). M is the mass of metal slab L is the thickness of non conductor [ Card board ] C is the specific heat of water. A is the cross sectional area of non conductor. T1 is the temperature of the bar near cold end. T2 is the temperature of the bar near hot end. T3 is the initial temperature of water [ Temperature of water at inlet ] T4 is the final temperature of water [ Temperature of water at outlet ] OBSERVATIONS: o Mean diameter of the bar = d =___________________ cm ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 60
Dated : _______________ o Radius of the bar = r = d / 2 = _________________ cm o Distance between two holes on the bar = L =________ cm o Temperature of the bar near cold end = T1 = __________ C o Temperature of the bar near hot end = T2 = __________ C o Temperature of water at inlet = T3 = ________________ C o Temperature of water at outlet = T4 = _______________ C o Mass of empty beaker = m 1 = ________________ grams. o Mass of beaker + water = m 2 = ______________ grams. o Mass of water collected = M = [ m 2 – m 1 ] = _____ grams. o Specific heat of water = C = 1 cal / grams C o Time for which M gram of water is collected = t = ____Sec S. NO
Time t (min)
1 2 3 4 5
0 05 10 15 20
T1 C
T2 C
T3 C
T4 C
CALCULATIONS: ML C [ T - T ] 4 3 A π r 2 K A [ T T ] 2 1 Actual Value [ Thermal conductivity of the given bar ] Copper 0.99 cal / sec / cm / C Percentage Of Error ASIFJAH ZEHRAVI
Actual Value Calculated Value 100 Actual Value
CELL 0300 – 2568922 & 0341 – 6623062 61
Dated : _______________ RESULT: The thermal conductivity of the material of the given bar by Searle’s apparatus is calculated to be __ cal / sec / cm / C Percentage of error = ___________________ %
___________________________
Teacher’s signature PRECAUTION: Least count of stop watch should be noted and graduation on stopwatch should be studied carefully before starting the experiment. Diameter of the metallic bar must be measured accurately. Sides of the bar must be well insulated by wrapping it in a thick coating of felt within the wooden box. Water must be circulated around the colder end of the bar at such a constant rate that there must be a temperature difference of at least 5C between inlet and out let water. Readings must be recorded when all thermometers show steady state. SOURCES OF ERROR : Inaccuracy of stopwatch. Diameter of bar may not be measured accurately. Bar may not be properly insulated due to which there may be loss of heat through sides of the bar. In accurate measurement of rate of flow of water.
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 62
Dated : _______________
EXPERIMENT NO . 18 OBJECT: To determine the specific rotation of sugar solution by Polari meter. APPARATUS: Polari meter, sodium lamp , pure cane sugar , balance , measuring cylinder , beaker , etc.
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 63
Dated : _______________ WORKING FORMULA: The specific rotation of sugar solution is given by
S
1000 m l
Where S is the specific rotation of sugar solution is the angle through which the plane polarized light is rotated by the sugar solution. m is the concentration of the sugar solution ( in % ) = Mass of sugar dissolved in 100 ml of distilled water. l is the length of the tube filled with the solution through which light is passed. OBSERVATIONS: o Least count of polarimeter scale = d =_________Degrees o Length of polarimeter tube = l = _____________ cm o Polarimeter reading for equally dark position with distilled water = “ 1” = ______________Degrees. S. NO
Strength of Polarimeter reading sugar for equally dark solution position with sugar solution “m”
“2”
1 2 3 4 5
% 1% 2% 3% 4% 5%
Angle of rotation
= [2 – 1] 1000
1
2
Mean
Deg
Deg
Deg
S
1000 m l
CALCULATIONS:
ASIFJAH ZEHRAVI
Specific rotation
ml Deg
Deg
CELL 0300 – 2568922 & 0341 – 6623062 64
Dated : _______________ Actual Value [ The specific rotation of cane sugar ] Cane sugar
Percentage Of Error
66.67
Actual Value Calculated Value 100 Actual Value
RESULT: The specific rotation of sugar solution at _____C is calculated to be ______________ Percentage of error = ___________________ %
___________________________
Teacher’s signature
PRECAUTION: Least SOURCES OF ERROR : Inaccuracy
ASIFJAH ZEHRAVI
CELL 0300 – 2568922 & 0341 – 6623062 65
