Free-response questions
Free-response questions will appear throughout both exams papers (Breadth and Depth), and at both Foundation Tier and Higher Tier.
These questions provide answer lines for you to write your answer and may sometimes also provide a blank space for you to draw a diagram or show your working out.
The number of answer lines and the number of marks for the question are guides to the amount of detail to include in your answer. A question worth one mark with only one answer line probably only requires a one-sentence answer, or perhaps just a single word or phrase. For questions with more marks and more answer lines you will have to go into more detail or give specific data points, eg:
- the speed of the object decreased [1 mark]
- the speed of the object decreased by 8 m/s [2 marks]
Free-response questions often start with a command word such as 'describe' or 'explain'. It鈥檚 important to understand the different types of answers required by 'describe' and 'explain'. As a rule of thumb:
- describe what happens, when and where
- explain how and why it happens (鈥渋t happens because鈥︹)
Other command words you might see include:
- 'write down' (give a short answer, without explaining it)
- 'suggest' (use your scientific knowledge and understanding to give a sensible answer in an unfamiliar context)
- 'compare' (write about the similarities and differences between two things)
- 'discuss' (write about the issues related to a topic, and talk about arguments for and against)
Learn about command words with Dr Alex Lathbridge
Listen to the full series on 大象传媒 Sounds.
Understanding the different command words in your science GCSE exams.
Sample question 1 - Foundation
Question
Sound waves travel through materials by making the particles in the material vibrate.
Use this idea and your knowledge of the particle model of matter to explain why sound travels much faster through water than through air. [2 marks]
OCR 21st Century Science, GCE Physics, Paper J259, 2016.
Particles are closer together in a liquid than in a gas, which makes it easier for vibrations to be transmitted through the material.
When answering any question that asks you to use the particle model, the first thing you should do in your answer is state how the particles are arranged. The next step is to explain how the particle model relates to the phenomenon in question.
Sample question 2 - Foundation
Question
Scientists can use seismic waves to find out about the structure of the Earth.
a) Scientists can tell when the rocks change by the refraction and reflection of waves. What is the effect of reflection on a wave? [2 marks]
b) What is the effect of refraction on a wave? [2 marks]
OCR 21st Century Combined Science, GCE Physics, Paper J260, 2016.
a) The wave changes direction - it does not pass through the boundary (bounces back).
The key to answering this type of question is not to be thrown by the context given in the question. Write down anything relevant you know about reflection for the best chance of getting all the marks available. Remember the context is the story - it does not change the science.
b) The wave changes direction - it passes through the boundary (bends as it travels through different medium).
The key to answering this type of question is not to be thrown by the context given in the question. Write down anything relevant you know about refraction for the best chance of getting all the marks available. Remember the context is the story - it does not change the science.
Sample question 3 - Higher
Question
X-rays are produced by firing particles at a metal target. The metal emits X-rays. What happens in the metal to produce X-rays? [2 marks]
OCR 21st Century Combined Science, GCE Physics, Paper J260, 2016 - Higher.
The electrons in the atom lose energy.
This is a straight recall question from the specification. The question is essentially asking how X-rays are produced, so you should say something along the lines of 'X-rays are produced when the electrons in an atom lose energy'. It is important to state that it is the electrons in the atoms that produce them.
Sample question 4 - Higher
Question
Increased levels of carbon dioxide in the atmosphere have been linked to the greenhouse effect. The graph below shows the amount of carbon dioxide in the atmosphere over a 1,000 year period.
Many scientists think this is evidence that human activity has had an effect on the amount of carbon dioxide in the atmosphere.
Explain how the graph supports this idea. [4 marks]
OCR 21st Century Science, GCE Physics, Paper J259, 2016 - Higher.
The graph shows a rapid increase in carbon dioxide around the same time that human activity/population/industry increased. Hence, a correlation is shown. The use of fossil fuels/deforestation means an increase in carbon dioxide in atmosphere.
In a question like this where it asks you to use the graph, the first thing you need to do is explain what the graph shows. Next you need to link it back to the question - what changed over the 1,000 year period that caused an increase in carbon dioxide? You then need to state that there is an apparent correlation between human activity and an increase in carbon dioxide in the atmosphere.