- Answer all questions in the spaces provided.
- You are supposed to spend the first 15 minutes of the 2½ hours allowed for this paper reading the whole paper carefully before commencing your work.
- Marks will be given for clear records of observations actually made, their suitability, accuracy and the use made of them.
- Candidates are advised to record their observations as soon as they are made.
- All working must be clearly shown where necessary.
- Mathematical tables and silent electronic calculators may be used.
Question one
This question has two parts A and B. Answer both parts.
PART A
- A retort stand, clamp and boss.
- A spiral spring.
- A stop watch.
- Three 100g masses.
Proceed as follows:
- Suspend a 100g mass at the end of the spring as shown in figure 1.
Fig. 1
Now give the mass a small vertical displacement and release so that it performs vertical oscillations. Time ten oscillations and determine the period T. Enter your results in table 1. - Repeat the experiment for the other values of mass and complete the table.
Table 1
Mass m (g) 100 200 300 Time for 10 oscillations (s) Periodic time T(s) - Given t)hat T = π√(m/K), where k is the spring constant, find the average value k for the spring. K (2mks)
PART B
You are provided with the following:-- A 250ml glass beaker
- A Bunsen burner
- A Thermometer
- A Stop watch
- A Tripod stand and a Wire gauze
- A measuring cylinder 100ml
- Water
Set the apparatus as shown in figure 2 below.
Fig. 2
- Measure 100cm3 of water and pour it into the beaker. Take the initial temperature of the water.
T0 = …………………………………………….°C (1mk)
Now heat the water to a temperature of 800C. switch off the gas tap and place a thermometer into the beaker and start the stop watch when the temperature is 65°C. Take the temperature T°C of water ever two minutes. Record your results in the table 2 below.
Table 2
Time, t(min) 2 4 6 8 10 12 14 Time, t(min) (T - T0) Log (T - T0) - Plot a graph of Log (T - T0) against Time (t). (5mks)
- Find the value of P of log (T - T0) when t = 0. (1mk)
- Determine N, where N is the antilog of P. (1mk)
- Calculate the temperature of the surrounding TR using the expression N = 65 – TR (2mks)
Question 2
Part A
You are provided with the following:-
- A lens and a lens holder.
- A candle.
- A white screen.
Proceed as follows:
- Set the apparatus as shown below.
- Place the white screen at a distance X = 100cm from the candle. Let the lens be at position P, adjacent to the lit candle.
- Move the lens towards the screen until an enlarged image of the candle is formed on the screen. Measure and record the distance u1.
- Move the lens to a second position Q where the image of the candle is sharp but diminished on the screen.
Measure and record the distance u2.
Hence determine the value of d = u2 - u1. - Repeat the procedure in (c) and (d) for either values of x = 95, 90, 85, 80cm. Complete table 2 shown below.
Table 2
x(cm) 100 95 90 85 80 u1(cm) u2(cm) d = u2 − u1(cm) y = d2(cm) (2 d.p)
x - On the grid provided, plot a graph of y against x. (5mks)
- Determine the value of x = x0, when y = 0. (1mk)
x0 = …………………………………………… cm - Given that k = xo, determine the value of k. (1mk)
PART B
You are provided with the following:-- A voltmeter
- A resistance wire labelled R mounted on a metre rule.
- A metre rule.
- A resistance wire labelled T mounted on a small piece of carton.
- Two dry cells and a cell holder.
- Six connecting wires, each with a crocodile clip at one end.
- A switch.
Proceed as follows;
- Measure and record the e.m.f. E0 of the cells connected in series, E0 = ____ v. (1mk)
- Connect the circuit as shown below. Point O on resistance wire P is at 50cm mark of the metre rule. A and B are points on resistance wire P such that AO = OB = X = 30cm.
- Close the switch. Read and record the potential difference V across AO
V = …………………………………………. Volts. (1mk) - The relationship between V and x is given by:
I/V = 35/x + 1/y
Determine the value of y. (2mks) - Use the e.m.f. E0 to determine the constant k, given that:
k = 8 (1mk)
35E0
CONFIDENTIAL
QUESTION 1
Each candidate should have:-
- A retort stand, clamp and boss
- A spiral spring
- A stop watch
- Three 100g masses
- A 250ml glass beaker
- A Bunsen burner
- A thermometer (-10 to 110°C)
- A tripod stand and wire gauze
- A measuring cylinder 100mll
- A source of heat
- Some water in a container about 500ml
QUESTION 2
Each candidate is required to have the following apparatus:
- A voltmeter (0 – 5V)
- A candle
- A white screen
- Two new dry cells
- Six connecting wires, each with a crocodile clip at one end.
- A switch.
- A lens and a lens holder. NB: Focal length = 20cm.
- A metre rule.
- A resistance wire labelled R mounted on a metre rule.
The physics teacher is required to mount a nichrome wire SWG 28 on a metre rule and label the wire R. The diameter of the wire is 0.36mm. - A resistance wire labelled T.
The Physics teacher is required to mount a nichrome wire SWG 28 on a small piece of carbon box and label it T.
The diameter of the wire is 0.36mm and its length is 60cm.
MARKING SCHEME
Question one
(a) Table 1
Mass m (g) | 100 | 200 | 300 |
Time for 10 oscillations, (s) | 4.75 | 6.74 | 8.02 |
Periodic time T (s) | 0.475 | 0.674 | 0.0802 |
Award 1mk for correct evaluation of T
Time, t(min) | 2 | 4 | 6 | 8 | 10 | 12 | 14 |
Temperature (T) °C | 61.0 | 57.0 | 53.0 | 51.0 | 49.0 | 47.0 | 45.0 |
(T - T0) | 38.0 | 34.0 | 30.0 | 28.0 | 26.0 | 24.0 | 22.0 |
Log (T - T0) | 1.580 | 1.531 | 1.477 | 1.447 | 1.415 | 1.380 | 1.342 |
- Plotting P = 2 marks
- Scale S = 1mk
- Labelling axes A = 1mk
- Line L = 1 mark with −ve gradient
(f) P = y-intercept
− 1.61 1 mk
Evidence form the graph
(g) N = the antilog of P
= antilog of 1.61
= 40.74°C 1mk
(h) N = 65 − TR
40.74 = 65 − TR 1 mark
TR = 24.26°C
Question two
x(cm) | 100 | 95 | 90 | 85 | 80 |
u1(cm) | 25.0 | 27.0 | 29.0 | 30.0 | 32.0 ±1.0cm |
u2(cm) | 71.0 | 64.0 | 61.0 | 52.0 | 48.0 ±1.0cm |
d = u2 − u1(cm) | 46.0 | 37.0 | 32.0 | 22.0 | 16.0 |
y = d2(cm) (2 d.p) x |
21.16 | 14.41 | 11.38 | 5.69 | 3.20 |
= 1 = 35 + 1
Download Physics Paper 3 Questions and Answers with Confidential - Mangu High School Mock Exams 2023.
Tap Here to Download for 50/-
Get on WhatsApp for 50/-
Why download?
- ✔ To read offline at any time.
- ✔ To Print at your convenience
- ✔ Share Easily with Friends / Students