Wave Interactions (OCR Gateway GCSE Physics: Combined Science)

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.

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

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

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

Fig. 18.4

Complete the ray diagram in Fig. 18.5 for green light. The focal point for red light F_R is shown.

Fig. 18.5

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Tick (✓) one box.

Long-sight
Short-sight

Explain your answer.

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