A single slit diffraction pattern is formed with white light. For what wavelength of light the $$3^{\text {rd }}$$ secondary maximum in diffraction pattern coincides with the $$2^{\text {nd }}$$ secondary maximum in the pattern of red light of wavelength 6000 $$\mathop A\limits^o $$ ?

A point charge $$\mathrm{Q}$$ is placed at the centre of the line joining two equal point charges $$+\mathrm{q}$$ and $$+\mathrm{q}$$. The value of $$Q$$ if the system of the charges is in equilibrium, is

If the charge on the capacitor is increased by 2 C the energy stored in it increased by 21%. Total original charge on the capacitor is

A nucleus breaks into two nuclear parts, which have their velocity ratio $$2: 1$$. The ratio of their nuclear radii will be