IGCSE Physics Revision

IGCSE Physics Sample Questions & Answers

Question 1: Forces & Motion

A car accelerates uniformly from rest to a speed of 25 m/s in 10 seconds.
(a) Calculate the acceleration of the car.
(b) Calculate the distance travelled during this time.

Answer:

Given:
Initial velocity $u=0m/s$
Final velocity $v=25m/s$
Time $t=10s$

(a) Acceleration
Formula: a=v−uta = \frac{v – u}{t}a=tv−u​

a=25−010=2.5 m/s2a = \frac{25 – 0}{10} = 2.5 \, m/s^2a=1025−0​=2.5m/s2

✔ Acceleration = 2.5 m/s²

(b) Distance traveled
Formula: s=ut+12at2s = ut + \frac{1}{2}at^2s=ut+21​at2

s=0×10+12×2.5×102s = 0 \times 10 + \frac{1}{2} \times 2.5 \times 10^2s=0×10+21​×2.5×102 s=12×2.5×100=125 ms = \frac{1}{2} \times 2.5 \times 100 = 125 \, ms=21​×2.5×100=125m

✔ Distance = 125 m

Question 2: Electricity

A bulb has a resistance of 20 Ω and is connected across a 10 V battery.
Find the current flowing through the bulb.

Answer:

Formula: I=VRI = \frac{V}{R}I=RV​

I=1020=0.5 AI = \frac{10}{20} = 0.5 \, AI=2010​=0.5A

✔ Current = 0.5 A

Question 3: Energy

A student lifts a 5 kg bag vertically through 2 m.
Calculate the work done against gravity (Take g=9.8 m/s2g = 9.8 \, m/s^2g=9.8m/s2).

Answer:

Formula: $W=mgh$

$$W=5\times 9.8\times 2=98J$$

✔ Work done = 98 Joules

Question 4: Waves

A wave has a frequency of 200 Hz and a wavelength of 1.5 m.
Calculate the wave speed.

Answer:

Formula: $v=f\lambda$

$$v=200\times 1.5=300m/s$$

✔ Wave Speed = 300 m/s

Question 5: Density

An object has a mass of 600 g and volume 250 cm³.
Calculate its density.

Answer:

Convert mass to kg: $600g=0.6kg$
Convert volume to m³: 250cm3=2.5×10−4m3250 cm³ = 2.5 \times 10^{-4} m³250cm3=2.5×10−4m3

Formula: ρ=mV\rho = \frac{m}{V}ρ=Vm​

ρ=0.62.5×10−4=2400 kg/m3\rho = \frac{0.6}{2.5 \times 10^{-4}} = 2400 \, kg/m^3ρ=2.5×10−40.6​=2400kg/m3

✔ Density = 2400 kg/m³