Six-mark questions
Six-mark questions are extended open response questions. These require longer answers than the structured questions with fewer marks. It is wise to plan your answer rather than rushing straight into it, otherwise you may stray away from the key points.
Six-mark questions are marked using a levels-based mark scheme because they are open ended. To gain full marks, you need to:
- support explanations using scientific knowledge and understanding
- use appropriate scientific words and terms
- write clearly, linking ideas in a logical way
- maintain a sustained line of reasoning, rather than getting lost or bogged down
You are likely to see command words such as:
- 'describe' - you need to give an account but no reason
- 'explain' - you must give reasons or explanations
- 'devise' - you must plan or invent a procedure using your scientific knowledge and understanding
- 'evaluate' - you must review information, including identifying strengths and weaknesses, and make a supported conclusion
Six-mark questions may be synoptic questions. These questions bring together ideas from two or more topics. For example, a question about atoms could include ideas about atomic structure, isotopes, radiation and nuclear reactions.
Remember that the topics covered in the first paper are assumed knowledge for the second paper, so questions in the second paper may need knowledge and understanding of those topics too.
The answers shown here give marking points as bullet points. You do not usually need to include all of them to gain six marks, but you do need to write in full sentences, linking them logically and clearly.
Writing six-mark answers with Dr Alex Lathbridge
Listen to the full series on BBC Sounds.
How to write six-mark answers in your science GCSE exams.
Sample question 1 - Foundation
Question
The table below shows the stopping distances for a car.
| Speed of car (m/s) | Thinking distance (m) | Braking distance (m) | Total stopping distance (m) |
| 8 | 6 | 6 | 12 |
| 16 | 12 | 24 | |
| 32 | 96 | 120 |
| Speed of car (m/s) | 8 |
|---|---|
| Thinking distance (m) | 6 |
| Braking distance (m) | 6 |
| Total stopping distance (m) | 12 |
| Speed of car (m/s) | 16 |
|---|---|
| Thinking distance (m) | 12 |
| Braking distance (m) | 24 |
| Total stopping distance (m) |
| Speed of car (m/s) | 32 |
|---|---|
| Thinking distance (m) | |
| Braking distance (m) | 96 |
| Total stopping distance (m) | 120 |
Analyse the data in the table and use it to describe the trends shown.
Suggest reasons for the differences in the patterns in the data. [6 marks]
OCR Gateway Science, GCE Physics, Paper J249, 2016.
Mathematical comparisons:
The thinking distance and braking distance do not increase at the same rate. This suggests that the thinking distance is dependent on reaction time which is constant. The braking distance is affected by speed of the car because it will have more kinetic energy (energy is proportional to speed squared) and will require more energy to stop. When the speed doubles, the thinking distance doubles. When speed doubles, the braking distance quadruples. This affects the overall stopping distance.
The total stopping distance at 16 m/s = 36 m
The thinking distance at 32 m/s = 24 m
Therefore, as speed increases, so does the thinking/braking/stopping distance.
Sample question 2 - Foundation
Question
Stopping distances are important for road safety.
The Highway Code uses diagrams to show stopping distances.
Look at the diagram.
There are two parts to the stopping distance:
- thinking distance
- braking distance
Both of these can be increased by different factors.
Explain in detail how road conditions, speed and alcohol can affect road safety. [6 marks]
OCR Gateway Science, GCE Physics, Paper B751, May 2012.
Poor road conditions such as rain, snow, ice, wet leaves or gravel increase braking distance. Friction is reduced due to less grip/friction/slippery road. There is no effect on thinking distance. Going downhill increases braking distance.
Higher speed will increase thinking distance, so a greater distance will be travelled at a higher speed during the same thinking time. The speed will increase braking distance as more kinetic energy will need to be absorbed by the brakes.
Alcohol will increase thinking distance as slower reactions increase the thinking distance. Braking distance is unaffected but stopping distance is increased.
Answering tip: Briefly plan the key points you want to include in your answer. For example:
- explain the effect of road conditions, eg weather (on braking distances)
- explain the effect of speed (on thinking and braking distances)
- explain the effect of alcohol (on thinking distance)
Sample question 3 - Higher
Question
Scientists collect evidence from the universe and develop theories to explain their observations.
Here are three absorption spectra showing red shift. The white arrows show the relative position of the same band in the absorption spectra of a star, a nearby galaxy and a distant galaxy.
Using your knowledge of red-shift, describe how the information in the diagrams supports the idea of the Big Bang model. [6 marks]
OCR Gateway Science, GCE Physics, Paper J249, 2016 - Higher.
The further away a galaxy is the more red shifted it is. This indicates that the Universe is expanding. If galaxies are moving away then the Universe must be expanding. If the whole universe is expanding then it must have started from a certain point where the Big Bang occurred. More distant galaxies are more red shifted than stars that are closer. Distant galaxies show the absorption lines moving towards the red end of the spectrum and dark bands moving towards the red end of the spectrum.
The evidence linking red shift to the Big Bang model is that red shift is caused by a change in frequency/wavelength of light. The changes in frequency and wavelength of light from distant galaxies shows that galaxies are moving away.
Answering tip: Briefly plan the key points you want to include in your answer. For example:
- compare red-shift to distance
- say what this means, eg galaxies moving apart
- say how this supports the Big Bang, eg expansion of Universe
Sample question 4 - Higher
Question
Rockets carry satellites into space.
These satellites can have different types of orbit around the Earth.
One type is a low polar orbit.
Another type is a geostationary orbit, which has an orbital period of 24 hours.
Describe and explain the differences in orbits, periods and speeds between geostationary orbits and low polar orbits. [6 marks]
OCR Gateway Science, GCE Physics, Paper B752, June 2013 - Higher.
Satellites in low polar orbit experiences a higher gravitational force and has a lower altitude, higher speed/acceleration and shorter period than geostationary orbits. Geostationary orbits travel around the equator. The uses of polar satellite include military, mapping, navigation and weather. The uses of geostationary satellites include navigation, communication and weather.
Answering tip: Briefly plan the key points you want to include in your answer. For example:
- give typical uses for satellites in these orbits
- give differences in altitudes, periods (orbit times) and speeds
- explain the differences in terms of gravitational forces, eg for a polar orbit
