In photoelectric effect, the photo current

If the potential difference across a capacitor is increased from $$5 \mathrm{~V}$$ to $$15 \mathrm{~V}$$, then the ratio of final energy to initial energy stored in the capacitor is

A body of mass 'm' and radius of gyration 'K' has an angular momentum 'L'. Then its angular velocity is

In Young's double slit experiment, the intensity at a point where path difference is $$\frac{\lambda}{6}$$ ($$\lambda$$ being the wavelength of light used) is $$I^{\prime}$$. If '$$I_0$$' denotes the maximum intensity, then $$\frac{I}{I_0}$$ is equal to $$\left(\cos 0^{\circ}=1, \cos 60^{\circ}=\frac{1}{\lambda}\right)$$