1. Waves are either transverse or longitudinal.Write either “transverse” or “longitudinal” in the space alongside each of the following descriptions.

[4]2. In this question, you will apply the laws of reflection for a plane mirror to a curved mirror.

This mirror is shown in Fig. 2.1. The normal at any point on this mirror is the line from that point to the point C.

Fig 2.1

Two rays have been drawn from the object O.On Fig. 2.1,(i) draw the normal to the mirror at M, [1](ii) draw the ray reflected from M, [1](iii) draw the ray reflected from P, [1]

[Total: 3]

3. Fig. 3.1 shows a view from above of waves on the surface of water in a water tank.

The wavefront AB is travelling in region P towards region Q, where the water is shallower

and the waves travel more slowly.

(a) Some time later, the wavefront has moved into region Q.

CD, CE and CF are suggested positions of the new wavefront.

(i) State which is the correct position of the new wavefront.

.................................................................................................................................................[1]

(ii) Explain your answer to (i).

......................................................................................................................................................

......................................................................................................................................................

......................................................................................................................................................

.................................................................................................................................................[3]

2

4. A water wave in a tank travels from a region where the speed of the wave is faster into a region where it is slower.Fig. 4.1 is a one-quarter scale diagram that shows the wavefronts in the region where the speed is faster.

Fig 4.1 (scale: 1.0 cm represents 4.0 cm)

(a) (i) Take measurements from the scale diagram in Fig. 4.1 to determine the wavelength of the water wave as it travels in the faster region.

wavelength = ................................................ [2](ii) The speed of the wave in the faster region is 0.39 m / s.Calculate the frequency of the wave.

frequency = ................................................ [2]

3

(b) On Fig. 4.1, draw lines that indicate the positions of the wavefronts of the water wave in the slower region. [2]

(c) State what happens to the frequency of the water wave as it passes into the slower region.

...................................................................................................................................................

.............................................................................................................................................. [1]

[Total: 7]

5. A ray of monochromatic light passes through the glass prism shown in Fig. 5.1.

Fig 5.1 (a) State what is meant by the term monochromatic.

..........................................................................................................................................

.................................................................................................................................... [1]

(b) State the name given to what happens to the ray at A.

.................................................................................................................................... [1]

(c) Use the values on the diagram to calculate the angle of refraction at A (The angles in a

triangle add up to 180°).

angle of refraction = ................................................ [1]

4

(d) Calculate the refractive index of the glass.

refractive index = ................................................ [3]

(e) Explain why the ray does not emerge into the air at B, but does emerge at C.

..........................................................................................................................................

..........................................................................................................................................

..........................................................................................................................................

.................................................................................................................................... [2]

f) An identical prism is stuck to the first prism using a transparent adhesive with the samerefractive index as the glass. This is shown in Fig. 5.2.

Fig 5.2

On Fig. 5.2, draw the path of the ray after it has reached B and until it has passed into the air again. [3]

[Total : 11]

6. (a) The following list contains the names of types of energy transfer by means of waves.

γ-rays, infra-red, radio/TV/microwaves, sound, visible light, X-rays

(i) Which one of these is not a type of electromagnetic wave?

..................................................................................................................................... [1]

(ii) State the nature of the wave you have named in (a)(i).

..................................................................................................................................... [1]

5

(iii) The remaining names in the list are all regions of the electromagnetic spectrum, but

one region is missing.

Name the missing region.

..................................................................................................................................... [1]

(b) A television station emits waves with a frequency of 2.5 × 108 Hz. Electromagnetic

waves travel at a speed of 3.0 × 108 m / s.

Calculate the wavelength of the waves emitted by this television station. State the

equation you use.

wavelength = ......................................................... [3]

[Total: 6]

7. Light travels from one optical medium to another. State the conditions necessary for total

internal reflection to occur at the boundary between the two media.

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . [2]

In an optics lesson, a Physics student traces the paths of three rays of light near the

boundary between medium A and air. The student uses a protractor to measure the various

angles.

Fig. 7.1 illustrates the three measurements.

6

Fig 7.1

7

(a) State which is the optically denser medium, A or air, and how you can tell this.

..........................................................................................................................................

.................................................................................................................................... [1]

(b) State in which medium the light travels the faster, and how you know this.

..........................................................................................................................................

.................................................................................................................................... [1]

(c) State the critical angle of medium A.

...................................................[1]

(d) State the full name for what is happening to ray 3.

...................................................[1]

(e) The refractive index of medium A is 1.49.

Calculate the value of the angle of refraction of ray 1, showing all your working.

angle of refraction = ................................................ [2]

(f) The speed of light in air is 3.0 × 108m / s.

Calculate the speed of light in medium A, showing all your working.

speed of light = ................................................ [2]

[Total: 10]

8

I. II. Alternative to practical: 1. An IGCSE student is investigating reflection from a plane mirror.

Fig 1.1The student is using a sheet of plain paper on a pin board. Fig. 1.1 shows the sheet of paper.

The straight line EF shows the position of the reflecting surface of a plane mirror standing

vertically on the sheet of paper. Line GH is a normal to line EF. Line JG marks an incident

ray and line GK is the corresponding reflected ray. The student marks the position of the

incident ray with two pins (P1 and P2) and uses two more pins (P3 and P4) to find the

direction of the reflected ray.

(a) (i) On Fig. 1.1 mark with two neat crosses, labelled P3 and P4, suitable positions for the

pins to find the direction of the reflected ray.

(ii) On Fig. 1.1 measure the angle of incidence i.

i= ............................................

9

(iii) On Fig. 1.1 measure the angle of reflection r1.

r1= ............................................ [3]

(b) (i) On Fig. 1.1 draw a line E'GF' such that the angle between this line and the line EGF

is 10°. Start with E' below the line EGF. The straight line E'F' shows a new position of the

reflecting surface of the plane mirror standing vertically on the sheet of paper.

The points labelled P5 and P6 mark the positions of two pins placed so that P5, P6

and the images of P1 and P2 appear in line with each other. P1 and P2 have not

been moved since the original set-up.

(ii) Using a ruler, draw a line joining the points labelled P5 and P6, and continue this

line to meet the line E'F'.

(iii) Measure the angle of reflection r2 between line GH and the line joining the points

labelled P5 and P6.

r2 = ............................................(iv) Calculate the angle through which the reflected ray has moved.

= ............................................(v) Calculate the difference between 2θ and .

θ is the angle between the two positions of the mirror.

difference between 2θ and = ............................................[3]

(c) Theory suggests that if the mirror is moved through an angle θ then the reflected ray will

move through an angle of 2θ.

State whether your result supports the theory and justify your answer by reference to

the result.

Statement ........................................................................................................................

Justification..................................................................................................................................

..........................................................................................................................................[2]

[Total : 8]

10

2. The IGCSE class is investigating refraction of light through a transparent block.

Fig. 2.1 shows a student’s ray-trace sheet.

Fig 2.1

(a) (i) On Fig. 2.1, label the point F at which the incident ray crosses the normal NM. Label

the other end of the ray E.

(ii) On Fig. 2.1, draw a refracted ray from F, at an angle of refraction r = 20°, to meet side

CD of the block. Label the point G at which this ray meets side CD of the block. [1]

(b) Predict and draw on Fig. 2.1 the line of the ray that emerges from the block at point G.

Label the end of your line H. [2]

11

(c) To obtain the correct positions for the emergent ray in this experiment, the student places

two pins P1 and P2 on line EF. He observes the images of P1 and P2 through side CD of the

block so that the images of P1 and P2 appear one behind the other. He places two pins P3 and

P4 between his eye and the block so that P3, P4 and the images of P1 and P2, seen through

the block, appear one behind the other.

(i) On Fig. 2.1, mark the positions of the pins P3 and P4 at a suitable distance apart for this

experiment. [1]

(ii) State two precautions that you should take in this experiment to obtain reliable results.

1. ........................................................................................................................................

2. ........................................................................................................................................ [2]

(d) The student repeats the experiment with the block turned through 90°, as shown in Fig.

2.2.He measures the angle of refraction r.

r = ................ 22°..................................... .

Fig 2.2

He suggests that the value of r should be the same in both experiments because the material

of the block has not changed. State whether the results support this suggestion. Justify your

answer by reference to the results.

statement ..................................................................................................................................

justification ..........................................................................................................................[1]

[Total: 7]

12