A student is performing an optics experiment using a glass slab. A laser beam is found to travel through the glass at a speed of \(2 \times 10^8\, m/s\). If the speed of light in air is \(3 \times 10^8\, m/s\), what is the refractive index of the glass slab ?
1.5
The refractive index of a medium is given by \(n = \dfrac{c}{v}\), where c is the speed of light in air and v is the speed of light in the medium.
Substituting values: \(n = \dfrac{3 \times 10^8}{2 \times 10^8} = 1.5\).
Therefore, the refractive index of the glass slab is 1.5.
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