A person is observing a bacteria through a compound microscope. For better analysis and to improve the resolving power he should

Two rods of same length \& material transfer a given amount of heat in 12 s when they are joined end to end. But when they are joined length wise parallel to each other they will transfer same amount of heat in same condition in time

A graph of magnetic flux $(\phi)$ versus current ( 1 ) is shown for four inductors A, B, C, D. Smaller value of self inductance is for inductor

An insulated container contains a monoatomic gas of molar mass ' $m$ '. The container is moving with velocity ' $V$ '. If it is stopped suddenly, the change in temperature is ( $R=$ gas constant)