When photons of energy $h v$ fall on a metal plate of work function ' $W_0$ ', photoelectrons of maximum kinetic energy ' $K$ ' are ejected. If the frequency of the radiation is doubled, the maximum kinetic energy of the ejected photoelectrons will be
If a star emitting yellow light is accelerated towards earth, then to an observer on earth it will appear
The magnitude of the magnetic induction at a point on the axis at a large distance ( $r$ ) from the centre of a circular coil of ' $n$ ' turns and area ' $A$ ' carrying current ( $I$ ) is given by
A metal sphere of radius ' $R$ ' and density ' $\rho_1$ ' is dropped in a liquid of density ' $\sigma$ ' moves with terminal velocity ' $v$ '. Another metal sphere of same radius and density ' $\rho_2$ ' is dropped in the same liquid, its terminal velocity will be