INSTRUCTIONS TO CANDIDATES
 Write your name and index number in the spaces provided.
 Mathematical tables and nonprogrammable calculators may be used.
 This paper consists of three questions.
 Attempt all the questions in the spaces provided.
 ALLOW working MUST be clearly shown.
QUESTION ONE
Apparatus
 stopwatch
 250ml beaker
 Rubber bung
 Thermometer
 Bunsen burner
 Tripod
 Gauze
 Retort stand and clamp
 Hot water
Figure 2.
Procedure

 Measure and record the ambient temperature, TA =…………………..ºC (1 mark)
 Fill an empty beaker with exactly 150ml of hot water (check the side scale of the beaker)
 Set up the apparatus as shown in figure 2. Ensure the thermometer is about 2cm above the bottom of the beaker.
 Record the initial highest temperature of water TH=………………….. ºC (1 mark)
 Start the stopwatch and time for every 2.0 minutes the temperature T of water. Record the temperature in Table 2 for 20 minutes
Time (t) in minutes 2 4 6 8 10 12 14 16 18 20 Temperature (T) in ºC (TT_{A})ºC Log_{10}(TTA) (2 d.p)  Plot a graph of Log10(TTA) against time (5 mark)
 From the graph determine:
 The Slope S (3marks)
………………………………………………………………………………………………………………………………………………………………………………………  The cooling constant , K of water given S=0.4343K (2 mark)
 The Slope S (3marks)
 Given that the specific heat capacity of water is 4.2J/g/0C determine the heat lost when the water cools to the temperature of the surrounding ( 2 mark)
 PART A
You are provided with the following apparatus : One resistor labelled R = 40Ω
 A wire labelled W mounted on milliameter scale
 A wire labelled S mounted on a milliameter scale
 One dry cell and a cell holder
 One jockey
 one centre zero galvanometer
 Eight connecting wires, four with crocodile clips at both ends
 A micrometer screw gauge
 A switch
Proceed as follows
 Determine the average diameter D, of the wire labelled W using the micrometer screws gauge provided.
D1 = ............................................................ mm (½ mark)
D2 = ............................................................. mm (½ mark)
D = D1 + D2 (in cm)
2 (1 mark)  Set up the apparatus as shown in the circuit diagram in figure 3 below.
Use the crocodile clips to fix length L, of wire labelled S at 50cm from the end connected to the galvanometer G.  Close the switch and use the jockey to touch one end of the wire W, and then the other end. The deflections on the galvanometer should be in opposite directions, if not check the circuit. Adjust the positions of the jockey along the wire W until there is no deflection in the galvanometer. Record the value of x and y.
x = ..................................................................... cm (½ mark)
y = .................................................................... cm (½ mark)  Record for other values of L in table 3 below
L (cm) 45 40 35 30 25 20 X (cm) Y (cm) y/x (3 d.p) 
 Plot a graph of y/x (yaxis) against L. (5 marks)
 Determine the slope, m of the graph. (2 marks)
 Given that K = 100D, determine the value of K. (2 marks)
 Plot a graph of y/x (yaxis) against L. (5 marks)
PART B
 You are provided with a lens P a lens holder a white screen and half metre rule.
Procedure Set the apparatus as shown in figure 4 below. Focus a sharp image of a distant object on the screen (e.g window frame). The object should be 10cm away.The object should be at least 10cm away.
 Set the apparatus as shown in figure 4 below. Focus a sharp image of a distant object on the screen (e.g window frame). The object should be 10cm away.The object should be at least 10cm away.
 Measure the distance x in cm between the lens and the screen at which a sharp image is obtained repeat this two times, using different objects and record your readings in table 4 below.
Object Distance X, (cm) 1 2  Calculate the average value of x (1 mark)
……………………  What is the physical significance of the result obtained in (iii) above? (1 mark)
……………………….
 Calculate the average value of x (1 mark)
PHYSICS CONFIDENTIAL
QUESTION ONE
 stopwatch
 250ml beaker
 Rubber bung
 Thermometer
 150 ml of boiling water
 Tripod
 Gauze
 Retort stand and clamp
 Hot water
QUESTION 2
PART A
 One resistor labelled R = 40Ω
 A wire labelled W mounted on millimetre scale (32 gauge)
 A wire labelled S mounted on a millimetre scale (28 gauge)
 One dry cell and a cell holder
 One jockey
 One centre zero galvanometer
 Eight connecting wires, four with crocodile clips at both ends
 A micrometer screw gauge
 A switch
PART B
 Lens and a lens holder (f=10cm)
 Half metre rule
 White screen
MARKING SCHEME
QUESTION ONE
Apparatus
 stopwatch
 250ml beaker
 Rubber bung
 Thermometer
 Bunsen burner
 Tripod
 Gauze
 Retort stand and clamp
 Hot water
Figure 2.
Procedure

 Measure and record the ambient temperature, TA = 4ºC (1 mark)
 Fill an empty beaker with exactly 150ml of hot water (check the side scale of the beaker)
 Set up the apparatus as shown in figure 2. Ensure the thermometer is about 2cm above the bottom of the beaker.
 Record the initial highest temperature of water TH= 83 ºC (1 mark)
 Start the stopwatch and time for every 2.0 minutes the temperature T of water. Record the temperature in Table 2 for 20 minutes
Time (t) in minutes 2 4 6 8 10 12 14 16 18 20 Temperature (T) in ºC 72 71 67 63 60 58 56 54 52 51 (TT_{A})ºC 48 47 43 39 36 34 32 30 28 27 Log_{10}(TTA) (2 d.p) 1.68 1.67 1.63 1.59 1.56 1.53 1.51 1.48 1.45 1.43  Plot a graph of Log10(TTA) against time (5 mark)
 From the graph determine:
 The Slope S (3marks)
G =Δy =1.65  1.45
Δx 4  18  The cooling constant , K of water given S=0.4343K (2 mark)
0.01429 = 0.4343K
K = 0.03289
 The Slope S (3marks)
 Given that the specific heat capacity of water is 4.2J/g/ºC determine the heat lost when the water cools to the temperature of the surrounding ( 2 mark)
H = Mcθ
M = 150cm^{3} x gm^{3}
= 150g
H = 0.15 x 4200 x 59
= 37.170J
 PART A
You are provided with the following apparatus : One resistor labelled R = 40Ω
 A wire labelled W mounted on milliameter scale
 A wire labelled S mounted on a milliameter scale
 One dry cell and a cell holder
 One jockey
 one centre zero galvanometer
 Eight connecting wires, four with crocodile clips at both ends
 A micrometer screw gauge
 A switch
Proceed as follows
 Determine the average diameter D, of the wire labelled W using the micrometer screws gauge provided.
D1 = 0.30 mm (½ mark)
D2 = 0.30 mm (½ mark)
D = D1 + D2 (in cm)
2 (1 mark)
= 0.30 + 0.3.0
2
= 0.30mm  Set up the apparatus as shown in the circuit diagram in figure 3 below.
Use the crocodile clips to fix length L, of wire labelled S at 50cm from the end connected to the galvanometer G.  Close the switch and use the jockey to touch one end of the wire W, and then the other end. The deflections on the galvanometer should be in opposite directions, if not check the circuit. Adjust the positions of the jockey along the wire W until there is no deflection in the galvanometer. Record the value of x and y.
x = 88.3 cm (½ mark)
y = 11.7 cm (½ mark)  Record for other values of L in table 3 below
L (cm) 45 40 35 30 25 20 X (cm) 92.6 93.5 94.5 95.0 96.0 96.5 Y (cm) 7.4 6.5 5.5 5.0 4.0 3.5 y/x (3 d.p) 0.080 0.070 0.058 0.053 0.042 0.036 
 Plot a graph of y/x (yaxis) against L. (5 marks)
 Determine the slope, m of the graph. (2 marks)
G =Δy =(8  0) x 10^{2} = 0.08
Δx 45  0 45
1.778 x 10^{3} cm  Given that K = 100D, determine the value of K. (2 marks)
K = 100 x 0.30
10
= 30mm
 Plot a graph of y/x (yaxis) against L. (5 marks)
PART B
 You are provided with a lens P a lens holder a white screen and half metre rule.
Procedure Set the apparatus as shown in figure 4 below. Focus a sharp image of a distant object on the screen (e.g window frame). The object should be 10cm away.The object should be at least 10cm away.
 Set the apparatus as shown in figure 4 below. Focus a sharp image of a distant object on the screen (e.g window frame). The object should be 10cm away.The object should be at least 10cm away.
 Measure the distance x in cm between the lens and the screen at which a sharp image is obtained repeat this two times, using different objects and record your readings in table 4 below.
Object Distance X, (cm) 1 10.0 2 10.0  Calculate the average value of x (1 mark)
10 +10 = 10cm
2  What is the physical significance of the result obtained in (iii) above? (1 mark)
Total length
 Calculate the average value of x (1 mark)
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