OCR GCSE Physics A (Gateway) Paper 4 Higher June 2019 question paper J249/04

A sound wave travels in air and enters water.

What happens to the sound wave as it enters the water?

An electromagnetic wave transfers energy.

Which row in the table is correct?

Which waves can damage cells and cause cancer?

A Radio, X-rays and infra-red.

B Sound, gamma-rays and microwaves.

C Sound, visible light and ultraviolet.

D Ultraviolet, gamma-rays and X-rays.

Which row in the table shows realistic speeds?

The table gives some information about four radioactive isotopes.

Which isotope is the best to use as a medical tracer?

The table contains descriptions of wavelength and frequency.

Which row in the table is correct?

Which statement shows energy resources that are all renewable ?

A Bio-fuel, wind, hydro-electricity and tides.

B Fossil fuels, bio-fuel, wind and hydro-electricity.

C Fossil fuels, nuclear fuel, hydro-electricity and tides.

D Nuclear fuel, bio-fuel, wind and tides.

Which statement is true for isotopes of the same element?

N_p = number of protons and N_n = number of neutrons.

A N_p = N_n

B N_p is the same but N_n is different

C N_p is always greater than N_n

D The total (N_p + N_n) is always the same

The table contains statements about red-shift and galaxies.

Which row in the table is correct?

All bodies emit electromagnetic radiation.

Body R is at a higher temperature than body S.

Which statement is correct?

A R emits radiation with a mean higher frequency.

B R emits radiation with a mean longer wavelength.

C S emits radiation with a higher intensity.

D S emits radiation with a mean shorter wavelength.

Planet Ocra is in a circular orbit around a star.

Which statement is correct?

A The acceleration of Ocra is zero.

B The speed of Ocra is changing.

C The velocity of Ocra is changing.

D The velocity of Ocra is zero.

An artificial satellite orbits the Earth in a circular path.

The satellite is moved further away from Earth to another orbit.

Which row in the table is correct?

A boiler has an input power of 12 kW from the gas it burns.

Its efficiency is 0.75.

Which row in the table shows the correct values for this boiler?

A car has a mass of 1000 kg and a kinetic energy of 12 500 J.

Calculate its speed.

Use the equation: kinetic energy = 0.5 × mass × (speed)²

A 3.5 m / s

B 5.0 m / s

C 6.3 m / s

D 25.0 m / s

A TV has a power rating of 0.2 kW.

Calculate the energy transferred, in kWh, if the TV is switched on for 4 hours.

A different TV works with a 12.0 V battery. It has a current of 3.19 A.

Calculate the power rating of the TV.

The graph shows thinking and braking distances for a car at different speeds.

Describe how thinking distance varies with increasing speed.

Use data from the graph in your answer.

Use the graph to find the thinking distance at 24 m / s.

Calculate the thinking time at 24 m / s.

Use your answer to (b)(i) and the equation: distance travelled = speed × time

Give your answer to 2 decimal places.

State one factor that could increase thinking distance.

Calculate the stopping distance at 15 m / s.

Use the graph to help you.

How does the speed affect the kinetic energy and braking distance of the car?

Use the graph in your answer.

A student investigates reflection and refraction of light rays.

The student sends a ray of red light into a glass prism.

Fig. 18.1 shows the light ray as it leaves the glass prism.

On Fig. 18.1 complete the ray of light as it travels towards and through the glass prism.

Fig. 18.2 shows two mirrors placed at 90° to each other.

A light ray hits one of the mirrors at 45°.

On Fig. 18.2 complete the ray of light as it reflects from both mirrors.

What colours are transmitted by filter X ?

What colours are absorbed by filter Y ?

A wall is painted red.

When some coloured lights shine on it, the wall appears black.

Explain why.

Suggest two different colours of light that would cause the wall to appear black.

An optician uses red and green light to test vision.

Fig. 18.4 is a ray diagram showing red light passing through a lens.

Explain your answer to (e)(i).

Is the lens in Fig. 18.4 and 18.5 suitable for correcting long-sight or short-sight?

Tick (✓) one box.

Explain your answer.

Nuclear fusion is a reaction that happens in stars. This equation for fusion is incomplete.

What else is produced in this reaction?

Stars are formed from dust and gas.

What causes the dust and gas to undergo fusion?

Describe one similarity between nuclear fission and nuclear fusion.

Describe one difference between nuclear fission and nuclear fusion.

Nuclear fission can be used as a power source to produce electricity.

Give one advantage and one disadvantage of using nuclear power to produce electricity.

advantage........

disadvantage........

Energy is transferred at high voltages in the national grid.

This house is near to a transmission line.

Explain why radio waves may be produced by the transmission line.

Explain why it is more efficient to transfer energy at high voltages.

The transmission line has a power loss of 6.156 kW.

Its resistance is 15.39 .

Calculate the current in the transmission line.

Fig. 21.1 is a speed-time graph for car P.

The driver of car P reacts to a traffic light at time = 0.00 s, then presses the brakes at time = 0.50 s.

The braking distance is the same size as the thinking distance.

Explain how the graph in Fig. 21.1 shows this.

Add another line to the graph in Fig. 21.1 to show the journey of car Q.

• Car Q is travelling at 8 m / s.

• The driver of car Q reacts, then presses the brakes after 0.75 s.

• Car Q decelerates at the same rate as car P.

Driver P measures the reaction time of driver Q using a 30 cm ruler.

Driver P drops a 30 cm ruler vertically and driver Q catches it.

Explain how the ruler can be used to estimate reaction time.

State one precaution they can use to get accurate results.

In the brakes of a car there are brake pads and a brake disc, as shown in Fig. 21.2.

When a car stops, energy transfers between stores.

The brake pads squeeze the brake disc and cause a friction force.

Explain how braking stops the car.

Include ideas about energy stores in your answer.

High speed cars have ventilated brakes with air holes in the disc, as shown in Fig. 21.3

The air holes allow more air to circulate around the disc.

Suggest how these brakes can reduce braking distances.

22* The Earth contains a crust, mantle and core as shown in Fig. 22.1.

Table 22.1 gives some data about seismic waves and the Earth.

Describe what information the data in Table 22.1 gives about the structure of the Earth.

In your answer you should explain any trends in the data in Table 22.1.

A teacher measures the activity of different radioactive isotopes.

Fig. 23.1 is a graph of her results for isotope A.

Use Fig. 23.1 to calculate the half-life of isotope A.

Show your working on the graph in Fig. 23.1.

Half-life =........ minutes

The teacher measures the activity of isotope B.

She starts taking activity measurements after 20 minutes.

Table 23.1 shows her results for isotope B.

Predict the activity of isotope B at 0 minutes.

Use the information in Table 23.1 to help you.

Activity =........ counts per minute

The teacher measures the activity of isotope C.

Fig. 23.2 is a graph which shows how activity varies with time for isotope C.

A student makes two conclusions from the graph in Fig. 23.2:

Conclusion 1: I think the results are very inaccurate. The isotope stops being radioactive and then gets more radioactive again.

Conclusion 2: I do not think the isotope has a half-life.

Is the student correct?

Evaluate each conclusion and explain your answer.

Some students try to measure the speed of sound, as shown in Fig. 24.1.

One student makes a loud sound by clapping her hands.

The sound of the clap reflects from the gym wall causing an echo.

Another student measures the time between hearing the clap and hearing the echo.

They repeat the experiment three times and record their results in the table below.

The student did not pay attention when recording time 3.

Calculate the mean time taken for the sound of the clap to return, using suitable values from the table.

Calculate the speed of sound for the clap.

Use your answer to (a)(i) and the equation: distance travelled = speed × time

Give your answer to 3 significant figures.

Speed of sound =........ m / s

Describe two ways to improve and develop their method.

Ultrasound wave pulses are used by vets to scan inner tissues inside animals.

The ultrasound pulses partially reflect from different layers of tissue. These reflected wave pulses (echoes) are collected by the detector as shown in Fig. 24.2.

In a scan using ultrasound pulses, three layers of tissue are detected, with each layer having a different thickness.

Describe and explain how the results from the detector can show:

• that there are three layers

• that each layer has a different thickness.