A beam of light of wavelength $$600 \mathrm{~nm}$$ from a distant source falls on a single slit $$1 \mathrm{~mm}$$ wide and the resulting diffraction pattern is observed on a screen $$2 \mathrm{~m}$$ away. The distance between the first dark fringe on either side of the central bright fringe is

An electron of mass '$$\mathrm{m}$$' and charge '$$\mathrm{q}$$' is accelerated from rest in a uniform electric field of strength '$$E$$'. The velocity acquired by the electron, when it travels a distance '$$\mathrm{L}$$', is

Two bodies have their moments of inertia I and 2I respectively about their axis of rotation. If their kinetic energies of rotation are equal, their angular momenta will be in the ratio

A ball kept at $$20 \mathrm{~m}$$ height falls freely in vertically downward direction and hits the ground. The coefficient of restitution is 0.4. Velocity of the ball first rebound is $$\left[\mathrm{g}=10 \mathrm{~ms}^{-2}\right]$$