PAPER2 SCHEME PHYSICS FORM4 SBP 2007 MID YEAR

SKEMA FIZIK KERTAS 2 PEPERIKSAAN DIAGNOSTIK PERTENGAHAN TAHUN 2007 SECTION A (52 M) QUESTION SUGGESTED ANSWER 1(a)(i)

MARK  

Ratchet

1

To prevent the user from exerting undue pressure on the object.

1

Second reading

1

To reduce (random) error TOTAL 1.5 cm / 20 = 0.075 cm = 0.75 mm

1 4 1

(b)

This method can improve the sensitivity of a meter rule so that it can measure up to a sensitivity of 0.01 mm / reduce error.

1

(c)

Systematic error – end error / zero error  Random error – parallax error 

1 1

Use micrometer screw gauge TOTAL

1 5

Diagram 3.1 – derived Diagram 3.2 – base

1 1 1

(b)

Diagram 3.1 – derived quantity is the quantity which can be defined in terms of other physical quantity Diagram 3.2 – base quantity is the quantity which cannot be defined in terms of other physical quantity

(c)

90 x 103 = 25 ms-1 3.6 x 103

1 1 6

(ii) (b) (i) (ii) 2 (a)

(d)

3 (a)

TOTAL

1

4 (a)(i)

Distance, unit meter  Time, unit second

1 1

(a)(ii)

Speed, ms-1

1

Distance = speed x time = 75 kmh-1 x 2 h = 150 km

1 1

(a)(iii)

1

(b)

5 (a) (b(i) b(ii) b(iii) c(i)

c(ii) c(iii)

6 (a)(i) (a)(ii) (a)(iii) (b)(i) (b)(ii) (b)(iii) (c)

V = 7 cm x 5 cm x 12 cm = 420 cm3 = 420 x 10-6 = 4.2 x 10-4 m3 TOTAL

1 1 7

Diagram 5.1 – the boy and skateboard move together in the same direction. Diagram 5.2 – the frog and leaf move in the opposite direction same Momentum before = momentum after  40 x 20 = (40 + 2) v v = 19.05 ms-1 The principle of conservation of momentum Momentum = m x v = 30 x 20 = 600 kgms-1

1

The boy has larger momentum than the girl

1

The boy has larger mass // the higher the mass, the higher the momentum

1

TOTAL Diagram 6.1 has less stretching force than Diagram 6.2 // Diagram 6.2 has more stretching force than Diagram 6.1 Diagram 6.1 has less work done than Diagram 6.2 // Diagram 6.2 has more work done than Diagram 6.1 Work done = ½ Fx = ½ (50) (0.2) =5J Diagram 6.1 has less energy than Diagram 6.2 Diagram 6.1 has less distance of projection than Diagram 6.2 The higher the energy gained, the higher the distance of  Use thicker elastic string // Increase the pulling force of arrow Acceleration ( a ) = -25/5 = -5 ms-2

1 1 1 1 1

9 1 1 1 1 1 1 1 1

TOTAL 7.(a)

1 1

8 1 1

2

(b)i

v

decreases

1

(ii)

25 ms-1 Show the extrapolation graph

1 1

c(i)

A = ½ (5)(25) = 62.5 m Displacement/distance of the car 

1 1 1

Deceleration

1

5s

1

( ii) d(i) (ii)

a

(iii)

-5

TOTAL

t

Pattern graph

1

Graph axis

1

12

3

SECTION B (20 M) 8.a (i) (ii)

 b.(i) (ii (ii) c.(i) (ii)

A way of representing a numerical value in the form of A X 10 n, where 1 ≤ A < 10 and n is is an integer  - The length of the rope is is approximately same as the the length needed so that the length is is not too long or too short. short.

1

- The density of the rope rope has to be small to make it light light

2

- The hardness of the rope rope should be more than the weight weight of parachutist to ensure that the rope is not easily break.

2

- The diameter of the rope has to to be moderate to make it comfortable comfortable to hold while controlling the parachute.

2

- The best choice is K because because the length is approximately approximately the same as needed, low density, snapping force is bigger than the load and moderate diameter  Scalar quantity is a physical quantity with magnitude only Vector quantity is a physical quantity with magnitude and direction.

2

Any exam exampl plee for for Vect Vector or quan quanttity ity – Di Displa splace cem ment, ent, acce accellerat eratiion Scalar quantity – Distance , speed 2 20 = 0 + ½ (10)t t=2s

2

1 1 1 1 1

v/ms-1 2

t/s a/ms-2

2 t/s TOTAL

20

4

SECTION C (28Marks) Question 9. a (i) a (ii) a (iii) b c

Answer scheme State the manipulated variable correctly ; Quantity of heat supplied / time for heating State the responding variable correctly ; Rise in temperature State one fixed variable; Mass of Water  θ = 25º C

Mark   1 1 1 1

Tabulate t and θ correctly in the table that shows t as manipulated variable and θ as the responding variable Gives √ base on the following aspect: A B C D

Shows a table which have t, θ  State the correct unit of  t, θ  All values of  t are correct Values of  , , θ  are correct

Give √ Give √ Give √ Give √

Scoring: Scoring: t / min 0 5 10 15 20 25

θ  / º C

25 36 47 58 69 80 4

(d)

Draw the graph of temperature, θ  against time ,t. A - The responding variable, θ at Y axis and manipulated variable, t at X axis:

Give √

B

- States the unit of the variable

Give √

C

- Both axes with the even and uniform scale: Give √

D

- 6 points correctly plotted: Give √√ Note: 4 – 5 points correctly plotted : Give √

E

- a smooth best fit straight line

Give √

5

F

- minimum size of the graph is 5 x 4 squares of 2 x 2 cm: ( From the origin to the last point)

G - title of the graph Number of √ 8 7 5-6 4 3 2 1 e

Give √

Give √ Score 7 6 5 4 3 2 1

State the correct relationship based on the candidate’s graph ( positive gradient straight line graph) The θ  increasing linearly with the t  TOTAL

Question 10. a(i) a(ii)

1

16

Answer Scheme State the relationship between T 2 and m correctly T 2 is directly proportional to m ( or  T 2 α m)

Mark   1

Calculate the Period, T  m = 55 g

T 2 = 3.6 S2

T  =

1.89 s Show horizontal line parallel to the axis with the m

a(iii)

7

1 1 1

Calculate the gradient of the graph and state the value within the acceptable range Show the triangle with an acceptable size ( 4 x 4 squares of 2 cm) Substitute correctly ( according to the candidate’s graph)

1

6

gradient = 3.25 - 0 s2 50 - 0 g

2

State the correct value of the gradient with unit 0.065 s2 g-1 (b)

c)

1

If  T  T = 1.2s T 2 = 1.44 s2

1

From the Graph if  T 2 = 1.44 s2 m = (22 ± 1) g

1

Show vertical line parallel to the axis with the T 2

1

State precaution to produce an accurate result of the experiment For every value of m, the experiment is repeated to obtain the average value of  T  Total TOTA TOTAL L MARK MARKSS FO FOR R SECT SECTIO ION N C (Q1 (Q1 + Q2) Q2)

1 12 28 m

7