In a Young's double slits experiment, the ratio of amplitude of light coming from slits is $$2: 1$$. The ratio of the maximum to minimum intensity in the interference pattern is:

The mean free path of molecules of a certain gas at STP is $$1500 \mathrm{~d}$$, where $$\mathrm{d}$$ is the diameter of the gas molecules. While maintaining the standard pressure, the mean free path of the molecules at $$373 \mathrm{~K}$$ is approximately:

The output from NAND gate having inputs A and B given below will be,

A $$10 ~\mu \mathrm{C}$$ charge is divided into two parts and placed at $$1 \mathrm{~cm}$$ distance so that the repulsive force between them is maximum. The charges of the two parts are: