OCR GCSE Physics A (Gateway) Paper 2 Foundation November 2021 question paper J249/02

Estimate the reaction time of a student.

A 0.02 s

B 0.2 s

C 2 s

D 20 s

Which of the following is a renewable energy source?

A Coal

B Hydro-electricity

C Nuclear fuel

D Oil

Which factor can affect the braking distance of a car?

A Age of driver

B Consumption of alcohol

C Mass of car

D Tiredness

A radioactive source has a count rate of 200 counts per minute (cpm).

The half-life of the radioactive source is 3 minutes.

What is the count rate of the radioactive source after 3 minutes?

A 0 cpm

B 100 cpm

C 200 cpm

D 400 cpm

The table shows the stopping distances for a car travelling at two different speeds.

The car now travels at 50 miles per hour.

Estimate the stopping distance.

A 28 m

B 53 m

C 73 m

D 88 m

Water waves are made in a ripple tank.

A student counts 4 waves passing a point per second.

What has the student worked out?

A Amplitude

B Frequency

C Period

D Wave speed

A force of 6 N moves through a distance of 3 m in the direction of the force.

Calculate the work done.

A 0.5 J

B 2 J

C 9 J

D 18 J

A student draws ray diagrams for some lenses.

Which ray diagram is correct?

A 3.0 kW oven is switched on for 1.5 hours.

Calculate the energy transferred by the oven.

Use the equation: energy transferred = power × time

A 2.0 J

B 2.0 kWh

C 4.5 J

D 4.5 kWh

A student calculates the change in the thermal energy of a 1 kg metal block.

The student heats the block and measures the change in temperature.

What other quantity is needed?

A Density of the metal

B Resistance of the metal block

C Specific heat capacity of the metal

D Volume of the metal block

This question is about electricity at power stations and at homes.

Which row in the table is correct?

The table shows two uses of electromagnetic radiation.

Which row in the table is correct?

A student makes a wave in a ripple tank.

The student measures distance, L.

What is the wavelength of the wave?

A 2.4 cm

B 4.0 cm

C 4.8 cm

D 24 cm

This question is about the solar system.

Describe how a planet’s orbit is different compared to a moon’s orbit.

The diagram shows the Sun.

Point P is inside the Sun.

Draw an arrow at P to show the direction of the force of gravity at P.

Label the arrow F.

Nuclear fusion reactions take place in the Sun. The energy released creates a force.

Draw an arrow at P to show the direction of this force.

Label the arrow R.

Explain why the size of the Sun does not change.

Write about force F and force R in your answer.

A 20 kg concrete block is lifted by a crane. The mass of one block is 20 kg.

Calculate the kinetic energy of the 20 kg block when it moves at 0.3 m / s.

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

The 20 kg block is lifted through a height of 16 m.

Calculate the gravitational potential energy gained by the 20 kg block.

Gravitational field strength is 10 N / kg.

The crane lifts blocks through a different height using an electric motor:

• The gravitational potential energy gained by the blocks is 0.6 MJ.

• The input energy of the motor is 1.5 MJ.

Calculate the efficiency of the motor.

Use the equation: efficiency = useful output energy transfer / input energy transfer

Explain why the efficiency of the motor is not 100%.

The crane’s lifting equipment contains moving parts. A workman suggests adding oil to these moving parts.

Explain how this will affect the efficiency.

A musician plays a guitar.

This makes a sound wave in the air.

The frequency of the sound wave is 440 Hz.

The speed of sound is 330 m / s.

Calculate the wavelength of the sound wave.

Use the equation: wave speed = frequency × wavelength

Explain how sound travels through the air from the guitar.

Write about air particles in your answer.

Fig. 18.1 is a graph of a sound wave.

Another sound wave has a higher frequency. The amplitude of the wave remains the same

Draw this sound wave on Fig. 18.2.

Plutonium-238 (Pu-238) is a radioactive element.

A scientist measures the activity of a sample of Pu-238.

The scientist takes five different measurements.

Table 19.1 shows their results:

What is the mode of the activity?

An alpha particle is emitted by Pu-238.

Complete the radioactive decay equation for Pu-238 decay.

A student says, ‘Alpha radiation is safer than beta.’

Do you agree with this student?

Tick (✓) one box.

Explain your answer.

A scientist is using a radioactive element. The scientist accidently touches the radioactive element and becomes contaminated.

The scientist stops using the radioactive element.

Explain why the scientist is still at risk.

Pu-238 can be used to generate electricity.

The power output generated increases with the mass of Pu-238.

This is a graph of power output against mass of Pu-238:

Use the graph to find the mass of Pu-238 needed for a power output of 460 W.

Pu-238 was used to generate electricity on a probe that went to Neptune.

The half-life of Pu-238 is 88 years.

Suggest why Pu-238 was used on the probe that went to Neptune.

A group of students compare the power of three kettles A, B and C using this method:

• They pour water in each kettle.

• They plug the kettles in and switch the kettles on.

• They measure the temperature of the water every 20 s.

• They calculate the change in thermal energy of the water every 20 s.

Each kettle has the same efficiency and is used for the same time.

Describe one other factor the students should control in their method.

How is energy transferred from the power station to the kettle?

In your answer write about:

• How electricity is distributed.

• The type of voltage used.

A student measures the speed of sound.

They use this equipment:

This is the student’s method:

• A sound is created when the hammer hits the metal plate.

• When the sound reaches microphone 1, the electronic timer starts.

• When the sound reaches microphone 2, the electronic timer stops.

• This process is repeated several times.

They record the time displayed on the timer in a table:

Calculate the mean time.

Give your answer to 2 significant figures.

They do not place the hammer and plate between the two microphones.

Suggest one reason why.

Another student repeats the same experiment.

These are the student’s measurements:

• The distance between the microphones is 2.4 m.

• The mean time measured is 7.5 ms.

Calculate the speed of sound.

Use the equation: distance travelled = speed × time

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

Describe how the student can measure the distance between the microphones.

The student looks up the speed of sound on a reliable website. They find the value for the speed of sound is 330 m / s.

Suggest why this is different from your value calculated in 21(c)(i).

This question is about visible light.

State one change that happens to light when it travels from water into air.

Diagram in Fig. 22.1 shows a ray of light from a fish in a container of water.

Complete the ray diagram in Fig. 22.1 to show the path of the ray after it leaves the water.

Include a normal line in your diagram.

Diagram in Fig. 22.2 shows three incident rays hitting the surface of the fish. Light is scattered from the surface of the fish.

Complete the diagram in Fig. 22.2 to show the scattered rays.

The fish appears red under white light.

Explain why the fish appears black under green light.

A solar cell changes light into electricity. Solar panels contain solar cells.

A student investigates a solar cell:

• They change the intensity of the light.

• They measure the potential difference across the solar cell.

The light intensity is changed to 2.00 W / m².

Use your graph to predict the potential difference of the solar cell.

Show your working on the graph.

Suggest one way the student could improve their investigation.

More people use solar panels to generate electricity compared to twenty years ago.

Suggest two reasons why.

A homeowner fits solar panels to the roof of their house.

Table 23.2 gives the energy values for the house for one day:

Explain whether the energy needed by all the appliances can be generated using only solar panels.

Use Table 23.2 and your knowledge of solar panels to explain your answer.