Wave Interactions (OCR Gateway GCSE Physics)

A student investigates reflection and refraction of light rays.

The student sends a ray of red light into a glass prism.

Fig. 18.1 shows the light ray as it leaves the glass prism.

On Fig. 18.1 complete the ray of light as it travels towards and through the glass prism.

Fig. 18.1

Fig. 18.2 shows two mirrors placed at 90° to each other.

A light ray hits one of the mirrors at 45°.

On Fig. 18.2 complete the ray of light as it reflects from both mirrors.

Fig. 18.2

White light is made of different colours.

White light passes through a transparent filter X.

Filter X absorbs green, blue, indigo and violet light.

The light then passes through another transparent filter Y, as shown in Fig. 18.3.

Fig. 18.3

The light that leaves filter Y is red.

[1]

[1]

A wall is painted red.

When some coloured lights shine on it, the wall appears black.

[1]

ii)

Suggest two different colours of light that would cause the wall to appear black.

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

An optician uses red and green light to test vision.

Fig. 18.4 is a ray diagram showing red light passing through a lens.

Fig. 18.4

Fig. 18.5

[1]

[1]

Tick (✓) one box.

Long-sight
Short-sight

Explain your answer.

[2]