4PH1/1PR — June 2023 (Edexcel IGCSE Physics): Past Paper

This question is about the electromagnetic spectrum.

The table gives some statements about the electromagnetic spectrum. Place three ticks (ü) in the table to show which statements are correct. Statement Correct all electromagnetic waves are longitudinal all electromagnetic waves travel at the same speed in free space radio waves have the longest wavelength in the electromagnetic spectrum x‑rays have the highest frequency in the electromagnetic spectrum all electromagnetic waves transfer energy all electromagnetic waves can cause cancer

Electromagnetic waves can be useful, but can also be harmful.

Give one use and one harmful effect of microwaves. use harmful effect

Give one use and one harmful effect of gamma rays. use harmful effect

The photograph shows the International Space Station (ISS) in orbit around the Earth. (Source: © Dima Zel/Shutterstock)

The ISS orbits the Earth in a circular orbit. Which of these also orbits the Earth?

Which of these forces causes the ISS to orbit the Earth?

The ISS completes one orbit of the Earth in a time period of 93 minutes.

The orbital radius of the ISS is 6.8 × 10³ km. Calculate the orbital speed of the ISS in km / s. orbital speed = km / s

Show that the ISS completes approximately 15 orbits of the Earth each day.

A model electric motor is used to lift a load through a vertical height. power supply electric motor joulemeter load

The load has a mass of 400 g and gains 3.2 J of energy in its gravitational store when lifted.

State the formula linking gravitational potential energy, mass, gravitational field strength (g) and height.

Calculate the height the load is lifted. height = m

State the amount of useful work done on the load by the motor when the load is lifted through this height. work done = J

The load is lifted at a constant speed. Diagram 1 shows the lifting force acting on the load as it is lifted. Draw a labelled arrow on diagram 1 to show the other force acting on the load. Ignore the effects of air resistance. lifting force load Diagram 1

A joulemeter measures the amount of energy transferred electrically to the motor as the motor lifts the load. The joulemeter displays a reading of 11.0 J when the load has gained 3.2 J of energy in its gravitational store.

Calculate the efficiency of the motor. efficiency =

Justify why 7.8 J of energy must be dissipated into the thermal store of the surroundings as the load is lifted.

Diagram 2 is an incomplete Sankey diagram. Complete the Sankey diagram to show the energy transferred by the motor. input energy wasted output energy Diagram 2

This question is about magnets.

Which of these substances is not attracted to a bar magnet?

Diagram 1 shows a bar magnet. NS Diagram 1 Draw magnetic field lines on diagram 1 to show the shape and direction of the magnetic field around the bar magnet.

Some bar magnets are made of steel. Explain why steel is a good material for making bar magnets.

Diagram 2 shows a cross‑section through a wire placed between two magnetic poles. The direction of the current in the wire is out of the page. S wire N Diagram 2

Draw an arrow on diagram 2 to show the direction of the force on the wire due to the magnetic field. Assume that the magnetic field is uniform.

State two changes that could be made that would decrease the magnitude of the force on the wire in diagram 2. 1 2

A car is travelling in a straight line along a road. The car passes a person standing at the side of the road. Before passing the person, the driver of the car presses the car’s horn. The horn makes a loud sound of constant frequency. The horn continues to make a sound until after the car has passed the person. Discuss the differences in the frequencies of the sound heard by • the driver of the car • the person at the side of the road

A student investigates how the current in a 60 Ω resistor varies with the voltage across the resistor.

The student has access to this equipment • 12 V battery • ammeter and voltmeter • 60 Ω resistor • variable resistor • switch • connecting wires Draw a circuit diagram to show how the student could connect this equipment to carry out the investigation.

No printed figure accompanies this part — in the paper you would draw the diagram (or label the apparatus) in the answer space provided.

Describe a suitable method the student could use for this investigation.

Complete the current–voltage graph by drawing a line that shows the expected results of the investigation. 0.30 0.20 Current in A 0.10 0.00 0 2 4 6 8 10 12 Voltage in V

The student repeats their investigation with a 120 Ω resistor. Explain how a current–voltage graph for a 120 Ω resistor compares with the current–voltage graph for the 60 Ω resistor.

Protactinium is an element with several different radioactive isotopes.

Protactinium‑234 has a half‑life of 6.7 hours. A sample of protactinium‑234 has an initial activity of 800 units.

Give a suitable unit for activity.

On the axes below, sketch a graph for the decay of the sample of protactinium‑234 during its first three half‑lives. 800 600 Activity 400 in 200 0 5 10 15 20 25 Time in hours

When protactinium‑234 undergoes beta ( β –) decay it becomes uranium‑234. The incomplete nuclear equation shows this process. 234 234 Pa 92 U + β Complete the nuclear equation to show the beta decay of protactinium‑234. Write your answers in the dashed boxes.

A student suggests an experiment to determine the type of radiation emitted by a different isotope of protactinium, protactinium‑231. This is the suggested method. Step 1 connect a suitable radiation detector to a radiation counter Step 2 place a source of protactinium‑231 at a fixed distance of 3 cm from the radiation detector Step 3 record the count of detected radiation for a time of one minute Step 4 place a sheet of paper between the source and detector Step 5 record the count of detected radiation for a time of one minute Step 6 repeat Steps 4 and 5 using a sheet of aluminium and then a sheet of lead instead of the sheet of paper The table shows the results of the investigation when it is done by a teacher. Material between source and detector Count no material 261 paper 14 aluminium 11 lead 13

Which of these is the dependent variable in the investigation?

The student’s method does not allow for background radiation. Describe how the student’s method should be modified to allow for background radiation.

Describe how the student’s method could be modified to improve the reliability of the results.

Evaluate the data from the experiment to conclude the type of radiation emitted by protactinium‑231.

Diagram 1 shows a set of masses attached to a spring, which is suspended from a support. support spring masses Diagram 1

After the masses are added, the length of the spring is 14.6 cm. The student measures the extension of the spring as 11.5 cm.

Calculate the original length of the spring. original length = cm

The student removes the masses and notices that the spring does not show elastic behaviour. Predict a value for the new length of the spring after the masses have been removed. new length of spring = cm

The student puts the masses back on the spring. The student then pulls the masses down and releases them. The masses vibrate up and down in a vertical direction, as shown in diagram 2. support spring vibrations masses Diagram 2 The distance–time graph shows how the distance between the top of the masses and the support changes with time as the masses vibrate. Distance Time

Explain how the gradient of the graph shows that the masses accelerate as they vibrate.

Add crosses (X) to the distance–time graph to show all the times when the masses are not moving.

The driver of a racing car makes a pit stop during a race to change the tyres on the racing car. The area where the tyres are changed is called the pit lane. (Source: © Hafiz Johari/Shutterstock)

Before entering the pit lane, the speed of the car must decrease for safety reasons.

The mass of the racing car is 830 kg. The maximum braking force is 41 000 N. Show that the maximum deceleration of the racing car is approximately 50 m / s².

The racing car is travelling at an initial speed of 72 m / s. Calculate the minimum distance needed to decrease the speed of the racing car from 72 m / s to 26 m / s. distance = m

The racing car slows down using its brakes. The brakes work using friction. The brakes become very hot when the racing car slows down. Using ideas about energy, explain why the brakes become hot.

The tyres of the racing car also get very hot during a race. A mechanic has to handle the hot tyres during the pit stop. They wear protective gloves which have several layers of insulating materials. Explain how the layers of insulating materials in the gloves reduce the risk of the mechanic burning their hands on the hot tyres.

A dam is a structure designed to hold water in a reservoir. dam water in a reservoir

The water in the reservoir has a depth of 35 m.

State the formula linking pressure difference, height, density and g.

Atmospheric pressure at the surface of the reservoir is 100 kPa. Calculate the total pressure at the bottom of the reservoir. [for water, density = 1000 kg / m³] pressure = kPa

An underwater camera is used in the water reservoir. The camera lens experiences a force of 430 N at a pressure of 260 kPa.

State the formula linking pressure, force and area.

Calculate the area of the camera lens. Give a suitable unit. area = unit

Sea water has a density of 1030 kg / m³. Explain how the design of the dam would need to be changed to hold the same depth of sea water safely.

The gravitational field strength of a planet decreases with increasing distance from the planet. The table shows the value of the gravitational field strength of Mars at different distances from the centre of Mars. Distance from centre of Mars in km Gravitational field strength in N / kg 4000 2.66 5000 1.70 6000 1.18 7000 0.87 8000 0.67 9000 0.53

A student finds this formula in a textbook, which links distance from the centre of a planet to its gravitational field strength gravitational field strength × distance² = constant Use data from the table to justify this formula.

Olympus Mons is the tallest mountain on Mars. The distance between the centre of Mars and the peak of Olympus Mons is 3410 km. Calculate the gravitational field strength at the peak of Olympus Mons. gravitational field strength = N / kg