Write an essay on Indian space programme.

(a) Define a wave front. Using Huygens’s principle, verify the laws of reflection in a plane surface.(b) In a single slit diffraction experiment, the width of the slit is made twice the original width. How does this affect the size and intensity of the central diffraction bond? Explain.(c) When a small circular obstacle is placed in the path of light from a distant source, a bright spot is seen at the centre of the obstacle. Explain why.

What is the Difference between Solenoid and Inductor?

Give a few applications of Faraday's law of induction in daily life.

A. Explain the ohmic loss in a conductor carrying a current where does the power come from?

B. α_R, α_ρ, and α are the temperature coefficient of resistance, temperature coefficient of resistivity, and coefficient of linear expansion of a conductor. Derive the relation between them.

C. What are the limitations of ohm’s law? Explain them.