What is angle of repose

Establish the relation angle of friction and angle of repose.

Establish the relationship between angle of repose and coefficient of friction

Establish the relation among deviation of a ray, angle of incidence and angle of refraction.

Establish the relation of angle of deviation with angleA,i_1 and i_2

Give the relation between critical angle and refractive index

Critical angle between a given transparent medium and air is theta_( c) . A ray of ligth in air enters the transparent medium at an angle of incidence equal to the polarising angle. Deduce a relation between angle of refraction r and critical angle theta_(c ) .

The relation between angle of the prism and refractive index of the medium is:

Deduce a relation between polarising angle and critical angle.

In case of a moving coil galvanometer, what is the relation between the current I and the angle of deflection theta ?