Physics P3 Questions and Answers - Butula Sub-County Post Mock Exams 2021/2022

INSTRUCTIONS TO CANDIDATES

• Write your name and your index number in the spaces provided above.
• This paper consists of two sections A and B
• Answer all questions in section A and B in the space provided
• All working must be shown in the spaces provided in this booklet.
• Mathematical tables and silent electronic calculators may be used

FOR OFFICIAL USE

QUESTIONS

Question one
You are provided with the following:

• A micrometer screw gauge (to be shared)
• A vernier calliper (to be shared)
• Glass tube
• A wire labelled M
• Some cello tape
• One 50 g mass
• Some masses totalling 40g
• A meter rule
• 100 ml beaker
• A stand boss and clamp
• A stop watch
• Candle
• A screen
• Some water
• measuring cylinder

PART A
Proceed as follows

1. Using a micrometer screw gauge , measure and record the diameter of the wire labelled M (2 mark)
   d= ……………………………………… mm
   d=………………………………………m
2. Using wire M make a spring as follows :
   1. Use some sellotape to fix one end of the wire M (about 2.5 cm) along the glass tube ;
   2. Hold firmly the part of the wireunder the tape with one hand. Use the other hand to wind 30 turns as closely and tightly as possible (see figure 1)
3. Remove the sellotape and release the spring from the tube
   (The spring will slightly unwind and some turns will disappear)
   Bend the free ends as shown in figure 2
4. Using a vernier callipers , measure and record the external diameter d of the spring (2 mark)
   D = ……………………………..cm
   D= ………………………………m
5. suspend the spring and a 50g mass from a retort stand as shown in figure 3
   Count and record the number of turns Nof the suspended spring (1mark)
   N =………………………..
6. Add 40g to the 50g record the extension X of the spring (2mark)
   X =……………………….. cm
   X =…………………….. m
7. Determine c given that(1mark)
   C= 0.4
          x
8. Determinen given that (2marks)
   C =  nd⁴  
        8ND³
9. With the spring still loaded with the 90g, pull the lower mass slightly downwards and let go so that the mass oscillates vertically. Record the time t for 20 oscillations. Hence determine the period T
   t= ……………………………… (s) (1mark)
   T =……………………………… (s) (1mark)
10. Determine Z given that
    T =2π√(m)
                (z)
    Where m is the mass in kg on the spring (2 marks)

PART B

1. You are provided with the following:
   • A candle
   • Metre rule
   • White screen
   • Lens holder
   • Convex lens

Proceed as follows:
(k)Place the lens on a metre rule. Arrange the set up as shown in the figure 4 below.

(l) Adjust the position of the lens so that it is a distance u = 30cm from the candle. Adjust the position of the screen until a well focused image of the flame is formed on the screen. Measure and record in the table 2, the image distance v, between the screen and lens.
(m) Repeat part (b) for other values of (u) shown in the table 1 and complete the table.

(5mks)
(n) Determine the mean value of y (2marks)

Question 2
PART A
You are provided with the following apparatus

• A voltmeter
• An ammeter
• A wire x mounted on a metre rule
• 8 connecting wires with crocodile clips
• Micrometer screw gauge
• A switch
• A jockey
• One new dry cell and a cell holder.

Proceed as follows:

1. Connect the apparatus provided as shown in the circuit in figure 5 below.
   
2. With the crocodile clip at L = 10 cm , close the switch S and record the ammeter and voltmeter reading.
   I =....................................................... (1 mark)
   V =..................................................... (1mark )
3. Repeat the procedure in (b) for other values of l = 10cm, 20cm, 30cm, 40cm, 50cm and 60 and recordthe readings in the table 2 below below. ( 5marks)
   

   Length. L. (cm)	10	20	30	40	50	60
   Voltmeter reading , V (volts)
   Ammeter reading , I(A)

4. Plot a graph of potential difference, V(y-axis) against the Current I .(5 marks)
   
5. Determine the slope of the graph (2marks)
6. Given that V= E – I r, use your graph to determine the value of;
   1. E (1mk)
   2. r (1mks)
7. Measure the diameter d of the wire x using the micrometer screw gauge. (1 mark)
   d =............................................ mm
   D.................................................m
8. Dismantle the apparatus and set up the circuit as shown figure 6 below.
   
9. Close the switch S and record the ammeter and the voltmeter readings (1mark)
   I =....................................................................
   V =................................................................
   Hence find R, the resistance of the wire x.
   R = ............................................................ (1mk)
10. Given that R = 4p
                            πd² 
    determine p (2 mks)

INSTRUCTIONS TO CANDIDATES

• Write your name and your index number in the spaces provided above.
• This paper consists of two sections A and B
• Answer all questions in section A and B in the space provided
• All working must be shown in the spaces provided in this booklet.
• Mathematical tables and silent electronic calculators may be used

FOR OFFICIAL USE

MARKING SCHEME

Question one
You are provided with the following:

• A micrometer screw gauge (to be shared)
• A vernier calliper (to be shared)
• Glass tube
• A wire labelled M
• Some cello tape
• One 50 g mass
• Some masses totalling 40g
• A meter rule
• 100 ml beaker
• A stand boss and clamp
• A stop watch
• Candle
• A screen
• Some water
• measuring cylinder

PART A
Proceed as follows

1. Using a micrometer screw gauge , measure and record the diameter of the wire labelled M (2 mark)
   

   d= 0.35 ±0.02 mm ½ mark each
   d=0.00035 …m ½ mark each

2. Using wire M make a spring as follows :
   1. Use some sellotape to fix one end of the wire M (about 2.5 cm) along the glass tube ;
   2. Hold firmly the part of the wireunder the tape with one hand. Use the other hand to wind 30 turns as closely and tightly as possible (see figure 1)
3. Remove the sellotape and release the spring from the tube
   (The spring will slightly unwind and some turns will disappear)
   Bend the free ends as shown in figure 2
4. Using a vernier callipers , measure and record the external diameter d of the spring (2 mark)
   

   D = ...0.81 ±0.2 cm ½ merk eachg
   D= …0.0084m

5. suspend the spring and a 50g mass from a retort stand as shown in figure 3
   Count and record the number of turns Nof the suspended spring (1mark)
   N =………………………..25 ± 2
6. Add 40g to the 50g record the extension X of the spring (2mark)
   

   X = 2.3 ±2cm 1 dp amust
   X =0.023 ±. M correct evaluation

7. Determine c given that(1mark)
   C= 0.4
          x
   ½ correct evaluation
   ½ four significant figures
8. Determinen given that (2marks)
   C =  nd⁴  
        8ND³
   Correct substitution 1 mark
   Correct evaluation 1 mark ignore units
9. With the spring still loaded with the 90g, pull the lower mass slightly downwards and let go so that the mass oscillates vertically. Record the time t for 20 oscillations. Hence determine the period T
   

   t= 8.84 ±0.5 (s) 2dp (1mark)
   T = 0.442 ± (s) corr eva (1mark)

10. Determine Z given that
    T =2π√(m)
                (z)
    Where m is the mass in kg on the spring (2 marks)
    Correct sub 1 mark
    Correc eval ( atleast 4sf) 1 mark

PART B

1. You are provided with the following:
   • A candle
   • Metre rule
   • White screen
   • Lens holder
   • Convex lens

Proceed as follows:
(k)Place the lens on a metre rule. Arrange the set up as shown in the figure 4 below.

(l) Adjust the position of the lens so that it is a distance u = 30cm from the candle. Adjust the position of the screen until a well focused image of the flame is formed on the screen. Measure and record in the table 2, the image distance v, between the screen and lens.
(m) Repeat part (b) for other values of (u) shown in the table 1 and complete the table.

(5mks)
(n) Determine the mean value of y (2marks)

Correct sub 1 mark
Correct evaluation 1 mark

Question 2
PART A
You are provided with the following apparatus

• A voltmeter
• An ammeter
• A wire x mounted on a metre rule
• 8 connecting wires with crocodile clips
• Micrometer screw gauge
• A switch
• A jockey
• One new dry cell and a cell holder.

Proceed as follows:

1. Connect the apparatus provided as shown in the circuit in figure 5 below.
   
2. With the crocodile clip at L = 10 cm , close the switch S and record the ammeter and voltmeter reading.
   

   I =.......0.14 ± 0.02 (1/2 mark)
   V =........0.25 ±0.05 (1/2 mark )

3. Repeat the procedure in (b) for other values of l = 10cm, 20cm, 30cm, 40cm, 50cm and 60 and recordthe readings in the table 2 below below. ( 5marks)
   

   Length. L. (cm)	10	20	30	40	50	60
   Voltmeter reading , V (volts) (1/2 each)	0.25	0.20	0.15	0.12	0.1	0.1
   Ammeter reading , I(A) (1/2 each)	0.14	0.12	0.10	0.10	0.08	0.07

4. Plot a graph of potential difference, V(y-axis) against the Current I .(5 marks)
   
5. Determine the slope of the graph (2marks)
6. Given that V= E – I r, use your graph to determine the value of;
   1. E (1mk)
   2. r (1mks)
7. Measure the diameter d of the wire x using the micrometer screw gauge. (1 mark)
   

   d =....0.25 ±0.05 mm ½ mark
   D...................m correct conversion

8. Dismantle the apparatus and set up the circuit as shown figure 6 below.
   
9. Close the switch S and record the ammeter and the voltmeter readings (1mark)
   

   I =...0.06 ± 0.021/2 mark each
   V =...............1.20 ± 0.05

   Hence find R, the resistance of the wire x.
   R = ..................Ω sub (1mk)
10. Given that R = 4p
                            πd² 
    determine p (2 mks)
    su 1 mark
    evaluation 1 mark