IGCSE Physics 0625 Paper 43, May/June 2026

Figure 1.1 shows a speed–time graph for a toy aircraft. Describe the motion between times: 18 s and 110 s .................................................................................................................... 110 s and 136 s. .................................................................................................................

Calculate the distance travelled between $\text{time}=0$ and $\text{time}=110\text{ s}$. $$\text{distance}=\text{..................................................... m}$$

Calculate the acceleration between $\text{time}=0$ and $\text{time}=18\text{ s}$. $$\text{acceleration}={\text{................................................ m/s}}^2$$

A small aircraft travels at a constant speed of $60\text{ m/s}$. The mass of the small aircraft is $820\text{ kg}$. Calculate the energy $E_{\mathrm{k}}$ in the kinetic store of the aircraft. $$E_{\mathrm{k}}=\text{...................................................... J}$$

Show that the moment of the $14\text{ N}$ force about the pivot is approximately $270\text{ N}\text{cm}$.

The brake pedal is stationary. The piston exerts a force of $72\text{ N}$ on the brake pedal. Calculate the distance $d$. $$d=\text{................................................... cm}$$

The pressure exerted by the brake fluid on the piston is $8.4\times {10}^4\text{ Pa}$. Calculate the cross-sectional area of the piston. $$\text{cross-sectional area}={\text{.................................................... m}}^2$$

Explain how the particles of helium gas in the balloon exert a pressure on the inside of the balloon.

The balloon contains a volume of $12{\text{ m}}^3$ of helium gas at a pressure of $110\text{ kPa}$. The balloon is released and rises to a height $h$ where the pressure of the gas is $52\text{ kPa}$. The temperature and the mass of helium gas remain constant. Calculate the volume of the helium gas at height $h$. $$\text{volume}={\text{.................................................... m}}^3$$

At height $h$, the balloon has gained $120\text{ kJ}$ of energy in the gravitational potential store. The mass of the balloon is $2.5\text{ kg}$. Calculate the height $h$. $$h=\text{..................................................... m}$$

Figure 4.1 shows a pan of water on a hotplate. The mass of water in the pan is $200\text{ g}$. The specific heat capacity of water is $4.2\text{ J}\mathrm{/}(\text{g}{}^{\circ }\mathrm{C})$. The temperature of the water increases from $22{}^{\circ }\mathrm{C}$ to $80{}^{\circ }\mathrm{C}$. Show that the energy transferred to the water is approximately $49\text{ kJ}$.

The time taken for the temperature of the water to increase from $22{}^{\circ }\mathrm{C}$ to $80{}^{\circ }\mathrm{C}$ is $41\text{ s}$. Calculate the minimum power of the hotplate. $$\text{power}=\text{..................................................... W}$$

State one reason why the power of the hotplate must be greater than the value calculated in 4(a)(ii).

Describe, in terms of particles and their motion, two ways in which a gas differs from a liquid. 1 ................................................................................................................................................ ................................................................................................................................................... 2 ................................................................................................................................................ ...................................................................................................................................................

Complete the sentence to describe a longitudinal wave. In a longitudinal wave, the direction of vibration is ......................................................... to the direction of propagation.

Give one example of a longitudinal wave.

A vibrating rod produces a water wave in a ripple tank. The wavelength of the wave is $0.016\text{ m}$. The wave is travelling at a speed of $0.12\text{ m/s}$. Calculate the frequency of the wave. Give the unit. $$\text{frequency}=\text{..................................}\text{unit ...............}$$

The water wave travels from shallow water to deep water. Complete Table 5.1 to show what happens to the properties of the water wave. Indicate your answers by placing ticks $(\mathrm{✓})$ in the appropriate boxes. One has been done for you. Table 5.1

Figure 5.1 shows a ripple tank demonstrating a wave effect. The wave passes through a small gap in a barrier. State the name of the wave effect shown in Figure 5.1.

State two changes that each increase the curvature of the wavefronts as the wave passes through the gap. 1 ........................................................................................................................................ 2 ........................................................................................................................................

An image of object O is formed by a plane mirror. A person views the image. Figure 6.1 shows a scale diagram of the arrangement. Mark the position of the image. Label it I.

Draw on Figure 6.1 to show the path of the light from object O to the person’s eye.

Figure 6.2 shows three rays of light travelling from a light source S. The rays travel in glass towards a glass–water boundary. Calculate the refractive index for the glass–water boundary. Use information from Figure 6.2. $$\text{refractive index}=\text{.........................................................}$$

On Figure 6.2, label the critical angle $c$.

On Figure 6.2, continue the path of ray X after it reaches the glass–water boundary.

The connecting wires in the circuit are made of metal. State the name of the particles that flow in the metal wires.

A bright light shines on component X. State the name of component X.

The resistance of component X is $400\mathrm{\Omega }$ when the light shines on it. Calculate the reading on the voltmeter. $$\text{reading on the voltmeter}=\text{...................................................... V}$$

The brightness of the light shining on component X is reduced. The resistance of component X increases. State the effect of this change on: the current in the fixed resistor ................................................................................................. the reading on the voltmeter. ....................................................................................................

A teacher uses the arrangement shown in Figure 8.1 to demonstrate how an intruder alarm works. Switch S is connected to a door. When the door is open, switch S is open. When the door is closed, switch S is closed. Complete the sentences to explain how the arrangement can be used as an intruder alarm. The teacher closes the door and the battery produces a ......................................................... in the coil of wire. The soft-iron bar is ......................................................... and attracts the soft-iron arm. When the door is opened, the contacts touch and this ......................................................... the bell circuit, causing the bell to ring.

Figure 8.2 shows a transformer that is 100% efficient. Calculate the voltage $V_{\mathrm{s}}$ across the secondary coil. $$V_{\mathrm{s}}=\text{...................................................... V}$$

A student connects the primary coil of the transformer to a d.c. supply. Explain why there is no voltage across the secondary coil.

Figure 9.1 shows a copper cylinder placed on two metal rods in the magnetic field between the poles of a magnet. The switch is closed. On Figure 9.1, mark with an arrow the direction of the current in the copper cylinder.

The copper cylinder moves to the left along the horizontal metal rods. Complete the sentences about pole X and pole Y. Pole X is a ......................................................... pole. Pole Y is a ......................................................... pole.

Suggest two changes that each increase the force on the copper cylinder. 1 ........................................................................................................................................ 2 ........................................................................................................................................

Figure 9.2 shows a d.c. motor. Explain how the split-ring commutator allows the coil to rotate continuously.

Explain the purpose of the brushes.

State the similarity and the difference between the composition of the nuclei of carbon-14 and carbon-11. similarity .................................................................................................................................... difference ..................................................................................................................................

A carbon-14 nucleus decays into a nitrogen (N) nucleus by the emission of a beta particle ($\beta$-particle). Complete the nuclear equation for the decay. $${}_6^{14}\text{C}\to \text{...............}+\text{...............}$$

State the change that occurs in the carbon-14 nucleus during the decay.

Scientists discover an ancient wooden object. The object contains $1.0\times {10}^{-10}\text{ g}$ of carbon-14. The object contained $8.0\times {10}^{-10}\text{ g}$ of carbon-14 when it was made. Carbon-14 has a half-life of $5700\text{ years}$. Estimate the age of the ancient wooden object. $$\text{age}=\text{............................................... years}$$

The Sun is an example of a stable star. Describe the process that releases energy in the Sun.

Complete the sentence about energy transferred from the Sun. The Sun radiates most of its energy in the infrared, visible and .............................................. regions of the .............................................. spectrum.

The Sun produces solar winds. Solar winds are streams of charged particles travelling through space. A charge of $240\text{ C}$ passes through a region of space in $180\text{ s}$. Calculate the current in this region of space. $$\text{current}=\text{...................................................... A}$$