P3 Physics revision questions Edexcel AQA GCSE

QUESTIONS

1.       What type of image do x-rays form?

2.   What radiation is used in PET scans?

3.       What is ionising radiation?

4.       Give two examples of ionising radiation using in medicine.

5.       State the equation for calculating the intensity of radiation.

6.       State 2 types of non-ionising radiation used in medicine?

7.       Label the diagram of the eye below

8.       What controls the amount of light entering the eye?

9.       What distance is your far point when focussing?

10.   Why does an image get blurred when it is nearer that 25cm to your eye?

11.   What is the job of the ciliary muscle

12.   Where does the image focus in a person who is short sighted?

13.   A person who is long sighted struggles to focus what objects?

14.   What lens shape is needed to correct short sightedness?

15.   What lens shape is needed to correct long sightedness?

16.   How does a converging lens change the path of a light ray?

17.   State methods other than glasses that can be used to correct vision problems.

18.   How can you permanently correct a person’s vision?  Explain how it works.

19.   What is the point at which converging rays meet called?

20.   What are the main causes of short sightedness?

21.   Define the term focal length.

22.   Where is the focal point in a diverging lens

23.   How is the power of a lens measured?

24.   What unit is used to measure the power of a lens.

25.   What is the lens equation?

26.   What factors are linked in the lens equation?

27.   Define a ‘real image’.

28.   Define a ‘virtual image’.

29.   State the law of reflection

30.   What is the ‘normal’?

31.   What is the definition of critical angle?

32.   Give three feature that help to maintain efficient diffusion in the lungs?  Explain how each affects the rate. (6 marks)

33.   How Automatic windscreen wipers work?

34.   What happens to the speed of a wave in denser materials?

35.   When a ray passes into a material where is can move faster does it refract towards or away from the normal?

36.   In Snell’s law what to nr and ni stand for?

37.   Why is a light ray in an optical fibre always reflected back?

38.   What is an endoscope and how does it work?

39.    State 3 ways ultrasound can be used in either diagnosis and treatment

40.   State the 3 main parts of an x-ray machine.

41.   If you increase the potential difference in the machine how does it affect the x-rays?

42.   What is Thermionic emission

43.   Complete the blanks below Increase temperature = _____________the electrons emitted = ____________ the X-rays produced.

44.   What is inverse square law?

45.   State 2 uses of fluoroscopes

46.   How does a CAT scan work?

47.   Give 2 benefits and 2 risks of X-rays, Fluoroscopes and CAT scans.

48.   How does a pacemaker work?

49.   Define the term action potential.

50.   What 2 things can a pulse oximeter tell us?

How to draw ray diagrams for convex/converging lenses GCSE Physics Revision

To draw an accurate ray diagram to figure out where the image will be formed, you need to follow these three rules:

1. Draw a ray from the top of the object that goes parallel to the principal axis (the line going horizontally through the centre of the lens). When the ray hits the lens, it then changes direction and passes through the focal point on the other side of the lens.

2. Draw a second ray that goes straight from the top of the object diagonally through the centre of the lens without changing direction.

3. Draw a third ray that passes from the top of the object, through the focal point on the left hand side of the lens and then changes direction when it hits the lens so that it travels parallel to the principal axis (straight line going through the middle) on the other side.