1. An unpolarized light beam is incident on the polarizes of a polarization experiment and the  intensity of light beam emerging from the analyzer is measured as 100 Lumens. Now, if the  analyzer is rotated around the horizontal axis (direction of light) by 30° in clockwise direction, the  intensity of emerging light will be________ Lumens.

2. A common transistor ratio set requires 12V (D.C) for its operation. The D.C source is constructed  by using a transformer and a rectifier circuit, which are operated at 220V (A.C) on standard  domestic A.C, supply. The number of turns of secondary coil are 24, then the number of turns of  primary are___________.

3. An electromagnetic wave of frequency 5 GHz, is travelling in a medium whose relative electric  permittivity and relative magnetic permeability both are 2. Its velocity in the this medium  is_____× 107 m/s.