When a polaroid sheet is rotated between two crossed polaroids then the transmitted light intensity will be maximum for a rotation of :

An object is placed in a medium of refractive index 3 . An electromagnetic wave of intensity $$6 \times 10^8 \mathrm{~W} / \mathrm{m}^2$$ falls normally on the object and it is absorbed completely. The radiation pressure on the object would be (speed of light in free space $$=3 \times 10^8 \mathrm{~m} / \mathrm{s}$$ ) :

The total kinetic energy of 1 mole of oxygen at $$27^{\circ} \mathrm{C}$$ is : [Use universal gas constant $$(R)=8.31 \mathrm{~J} /$$ mole K]

The truth table of the given circuit diagram is :