NumericalModerate1 mark
4(ii)
A type of glass block has a refractive index of 1.8.
If the width of this block is doubled, then what will be the speed of light in the block?
Topic: Speed of light and thickness of medium
Question wording verified against source paper
Answer
Exam answer
1.67 × 10⁸ m s⁻¹; it remains unchanged.
Explanation
The speed of light in a medium depends on its refractive index, not on the width of the block.
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