The process that absorb heat: i. Melting ii. Boiling/Evaporation iii. Sublimation
MARK 4
TOTAL
3
The process that release heat: i. Freezing ii. Condensation
2
c
Absorption of heat/ liquid changes and becomes gas.
1
a
Conduction
1
b
R→P→Q
1
c 3
a
b c.
d
4
i. ii. i. ii.
Rod R The material is a poor conductor of heat P Dull and black surface absorbed heat better than shiny surface. Through radiation A white surface is is a poor absorber of heat heat ( 1 ) Therefore, by wearing a white shirt shirt on a hot day, he will will not feel too hot hot ( 1 ) i. ii.
Paint the house with bright /white colours. White or bright colour is a poor absorber of heat. The white or bright colour prevents the houses from being too hot by reflecting the heat away from the house
3
1 2
2
7
Manipulated variable : Type of sheet material Responding variable : Final temperature
2
b
X = 76 celcius Y = 84 celcius
2
c
X = 24 celcius
d
Materials
1
e
Iron sheet
1
f
i. 70 celcius
ii. Cooper
5
1 1
a
Y= 16 celcius
8
2
iii. iron
2
10
5
a
Through conduction
b
i. ii.
c 6
a
b
i. ii.
1
R , P ,Q Time taken for thumbtack Q to drop is less than time taken for thumbtack P and R // Thumbtack Q drop first compare to thumbtack P and R. aluminium aluminium can absorb heat better/ faster .
i.
Student in Situation A received heat more than student in Situation B. ii. he black color is the best heat heat absorber than the white color. i. Tin Initial Final 0 X 28.6 C 350 C 0 o Y 28.6 C 60 C
1
2 1 2 1 1
2
ii. Tin X Y
Initial 0 28.6 C 0 28.6 C
Final 0 35 C o 60 C
Rise o 6.4 C o 31.4 C
2
c
2
Manipulated: Type of surface color//surface color Responding: Thermometer reading//temperature reading//temperature reading//the reading//the rises of temperature Control : Volume of water//initial temperature//the distance of bunsen burner// d
The darker the surface the higher the heat absorbed
