4PH1/2P — January 2020 (Edexcel IGCSE Physics): Past Paper

This question is about energy resources.

The table lists some methods of generating electricity using energy resources. Place ticks (✓ ) in the table to show if each method uses a renewable energy resource. One has been done for you. Method of generating Uses a renewable electricity energy resource coal power station diesel generator geothermal power station hydroelectric power station natural gas turbine nuclear power station solar cell ✓ wind turbine

Solar cells can be used to generate electricity.

How is energy transferred from the Sun to a solar cell?

State one disadvantage of using solar cells to generate electricity.

The photograph shows a brass mass. © Dudaeva/Shutterstock

State the formula linking density, mass and volume.

The brass mass has a mass of 454 g. The density of brass is 8.46 g/cm³. Calculate the volume of the brass mass. Give the unit. volume = unit

Curling is a sport played on ice. A player slides stone A across the ice towards a scoring zone. The ice reduces friction so that there is negligible friction when the stone is sliding. stone A © Corepics VOF/Shutterstock

Stone A leaves the player’s hand with a velocity of 2.90 m/s. The mass of stone A is 17 kg.

State the formula linking momentum, mass and velocity.

Show that the momentum of stone A is approximately 50 kg m/s.

Stone A slides towards the scoring zone. In the scoring zone, stone A collides with a stationary stone, B. © Michael715/Shutterstock

After the collision, both stones move in the same direction as the initial direction of stone A. The velocity of stone A after the collision is 0.40 m/s. Calculate the velocity of stone B after the collision. [mass of stone B = 19 kg] velocity of stone B = m/s

When the stones collided, they were in contact for a time of 25 ms. Calculate the magnitude of the force stone A exerted on stone B in this collision. force = N

A student uses this apparatus to demonstrate the effect of electric charge. funnel plastic tubing metal cap metal can insulator metal rod thin piece of metal He pours some fine powder into a funnel. The fine powder moves through a length of plastic tubing and falls into a metal can. The metal can rests on a metal cap. The metal cap is connected to a thin piece of metal via a metal rod. When the powder lands in the can, the thin piece of metal moves away from the metal rod.

Explain why the thin piece of metal moves away from the metal rod.

A coulombmeter measures electric charge. The student connects a coulombmeter to the metal can. When all the powder has landed in the can, the coulombmeter shows a reading of –9.4 × 10–9 C.

Which statement is true for the metal can?

State the formula linking charge, current and time.

It takes a time of 12 s from when the powder starts landing in the metal can until all the powder has landed in the can. Calculate the mean charging current. current = A

The student suggests that this demonstration is similar to refuelling an aircraft. The powder represents the fuel and the metal can represents the fuel tank in the aircraft. funnel plastic tubing metal cap metal can insulator metal rod thin piece of metal Explain how the student should modify this apparatus to demonstrate how to minimise the dangers when refuelling an aircraft. You may add to the diagram to help your answer.

A sonometer is a piece of equipment used to investigate the frequency of waves on a string. The photograph shows a sonometer. bridge string length of string The string is under tension. When the string is plucked it vibrates to produce a sound wave.

Describe how an oscilloscope should be used to measure the frequency of the sound wave from the sonometer.

A student investigates how the frequency of sound from the sonometer varies with the length of the string. This is the student’s method.

• apply a constant tension force to the string
• pluck the string and measure the frequency of the sound wave produced
• move the bridge to change the length of the string
• pluck the string and measure the new frequency of the sound wave produced Repeat the method for different lengths of string.

Give a control variable for the student’s investigation.

The table shows the student’s results. String Frequency in Hz length in cm Test 1 Test 2 Test 3 Mean 20 105 104 108 106 40 53 54 52 53 60 36 32 35 80 25 28 26 26 100 22 20 21 21 120 20 17 18 18 140 15 15 14 15 Calculate the mean frequency for a string length of 60 cm. mean frequency = Hz

Plot a graph of the mean frequency and string length data on the grid.

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

Draw the curve of best fit.

Determine the string length needed to produce a sound wave of frequency 75 Hz. string length = cm

The student cannot hear the sound from the sonometer for some of the string lengths tested. Explain which of the string lengths produce sounds that humans cannot hear.

This question is about stars.

Astronomers measure the absolute magnitude of stars. State what is meant by the term absolute magnitude.

The evolution of stars can be shown on a Hertzsprung‑Russell diagram (HR diagram). Complete the HR diagram by ● labelling the x‑axis ● completing the absolute magnitude scale ● drawing the main sequence, red giant and white dwarf regions absolute +5 magnitude blue white yellow red

The photograph shows a glass plate made from uranium glass. © Laura Healey/Shutterstock Uranium oxide is used to give the glass a green colour.

Uranium‑238 is the most common isotope of uranium and can be represented using this symbol. 238 92 U

State what information the numbers 92 and 238 give about the nucleus of this isotope of uranium. 92 238

Uranium‑238 decays by alpha emission. Describe how the nucleus of a uranium‑238 atom changes as a result of alpha emission.

The table gives some information about the uranium glass plate. mass of plate 1.1 kg percentage (%) of plate made of uranium-238 (by mass) 4.5% mass of uranium‑238 atom 4.0 × 10–27 kg

Calculate the number of uranium‑238 atoms in the plate. number of atoms =

Uranium‑238 is an alpha emitter and has a half‑life of 4.5 billion years. Explain why it is safe to eat food from the uranium glass plate.

This question is about magnetic fields.

Diagram 1 shows a positively charged proton moving downwards in a uniform magnetic field. magnetic field proton force velocity Diagram 1 The proton experiences a force to the right. What is the direction of the magnetic field?

When a current passes through a flat circular coil, a magnetic field is produced. Complete diagram 2 by drawing the magnetic field of the flat circular coil. to d.c. power supply Diagram 2 for the last part of the question

A wireless charging base uses a magnetic field to charge the battery of a mobile phone. wireless charging base mobile phone © BeeBright/Shutterstock There is an alternating current in a coil of wire in the charging base. There is another coil of wire connected to the battery in the mobile phone.

Explain how the wireless charging base charges the battery of the mobile phone.

Discuss the advantages and disadvantages of using a high current in the wireless charging base.