4PH1/2P — June 2019 (Edexcel IGCSE Physics): Past Paper

Which force is responsible for keeping satellites in orbit?

Which of these is the largest?

Which of these represents the brightness of stars at a standard distance?

A student investigates a transformer. This is the student’s method.

• use a primary coil with 10 turns
• connect the primary coil to a constant maximum input voltage
• measure the output voltage across the secondary coil
• repeat using an increasing number of turns on the primary coil The table shows the student’s results. Number of turns Output voltage on primary coil in V 10 39.6 20 19.7 40 9.9 60 6.6 80 5.0 100 4.0

Plot a graph of the student’s results on the grid.

Draw a curve of best fit. Output voltage in V 20 0 20 40 60 80 100 Number of turns on primary coil

Describe the relationship between the output voltage and the number of turns on the primary coil.

State the formula linking input and output voltages and the turns ratio for the transformer.

The input voltage of the transformer is 6.8 V. Calculate the number of turns on the secondary coil. number of turns =

This question is about sound waves.

Describe an experiment to measure the speed of sound in air. You may draw a diagram to help your answer.

An oscilloscope can be used to determine the frequency of a sound wave. The diagram shows an oscilloscope trace of a sound wave. Oscilloscope settings y direction: 1 square = 1 V x direction: 1 square = 0.25 ms

Calculate the period of this sound wave. period = s

Calculate the frequency of this sound wave. frequency = Hz

This is a question about alpha particles.

Describe the nature of an alpha particle.

The diagram shows the path of an alpha particle as it passes close to a nucleus. X nucleus

Draw an arrow from point X to show the force on the alpha particle due to the nucleus. Label this force Y.

Draw an arrow to show the force on the nucleus due to the alpha particle. Label this force Z.

Explain how the path of the alpha particle shows whether the nucleus is positive, negative or neutral.

The alpha particle experiences a resultant force of 3.6 N and has a mass of 6.6 × 10⁻²⁷ kg. Calculate the acceleration of the alpha particle. acceleration = m/ s 2

A toy produces continuous waves when floating on the surface of a pool of water. The waves spread out as circular wavefronts. Diagram 1 shows the wavefronts produced when the toy is not moving, as viewed from above. toy Diagram 1 Diagram 2 shows the wavefronts produced when the toy is moving across the surface of the pool of water. toy B A Diagram 2

Draw an arrow on diagram 2 to show the direction the toy is moving.

Explain how the frequency of the waves at point A is different to the frequency of the waves at point B.

A dog sits on a water‑filled bag to keep cool. water-filled bag

The table shows some data about the dog and the water in the bag. mass of water in kg 8.7 power output of dog by heating in W 75 specific heat capacity of water in J/kg °C 4200 initial temperature of water in °C 16 The dog sits on the bag for 22 minutes.

Calculate the energy transferred from the dog to the water by heating in 22 minutes. energy = J

State an assumption you have made when calculating the energy transferred.

Calculate the temperature of the water after 22 minutes. temperature = °C

Discuss why conduction is the main way that thermal energy is transferred from the dog to the water.

Give two pieces of evidence for the Big Bang theory.

Explain how this evidence supports the Big Bang theory.

The diagram shows a bottle supported by a finger. force from finger = 2.1 N not to scale 3.2 cm 28 cm Z floor weight of bottle

State the name of point Z.

State the formula linking moment, force and perpendicular distance from the pivot.

The bottle does not move. Calculate the weight of the bottle. weight of bottle = N

This is a question about a melting ice cube.

The diagram shows an ice cube placed on the ground. ice cube ground

The mass of the ice cube is 3.7 g and its area of contact with the ground is 2.6 × 10⁻⁴ m². Calculate the pressure the ice cube exerts on the ground. pressure = Pa

The ice cube melts and becomes a puddle with a larger cross‑sectional area. Explain how the pressure of the ice cube on the ground changes when it melts.

Ice melts at a temperature of 0 °C. On the axes, sketch how the temperature of the ice cube changes as it rises from a temperature of –10 °C to a temperature of 20 °C. Temperature in °C Time –10

Explain the changes that occur when a solid melts. Refer to particles in your answer.