Two wires P and Q each of same length and the same material are connected in parallel to a battery The diameter of P is half that of Q What fraction of the total current passes through P.
In a spectrometer experiment monochromatic light is incident normally on a diffraction gratin having 4.5 x 105 lines per metre The second order line is seen at an angle of 30 o to The normal What is the wavelength of the light.