If biconvex lens behave like plane sheet, ray will pass undeviated through it only when medium has same refractive index as that of biconvex lens.
When a biconvex lens of glass having refractive index 1.47 is dipped in a liquid, it acts as a plane sheet of glass. This implies that the liquid must have refractive index
Held on 30 Apr 2012 · Verified 9 Jul 2026.
equal to that of glass
less than one
greater than that of glass
less than that of glass
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The refractive index of glass is 1.5. The speed of light in glass is:
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