Q)
a) A bubble inside a glass slab appears to be at a depth of $3\;cm$ from one face and $2\;cm$ from opposite face. If $\mu= 1.5,$ what is the actual thickness of the slab?
b) An astronomical telescope consists of two thin lenses set $36\;cm$ apart and has a magnifying power of $8$. Calculate the focal lengths of the lenses.
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