The diagram shows lens arrangement in
In a given circuit, the cell P has an emf 1.5V and an unknown internal resistance while cell Q has an emf 2.0V and an internal resistance of 1 ohm if the ammeter reads 50m A, Then r is equal to
An air column 10cm in length is trapped into the sea end of a capillary tube by a 15cm column of mercury with the tube held vertically as shown above. On inverting the tube the air column becomes 15cm long. The atmospheric pressure during the experiment is
In a resonance tube experiment, which is illustrated above, the velocity of sound in air is 327.68m/s, the frequency of the turning fork used is therefore?