Electric Charges and Fields — Physics STD 12 Science — Question

A monkey is sitting on a tree limb. The limb exerts a normal force of 48N and a frictional force of 20N. Find the magnitude of the total force exerted by the limb on the monkey.

Write the mathematical relation between mobility and drift velocity of charge carriers in a conductor. Name the mobile charge carriers responsible for conduction of electric current in (i) an electrolyte (ii) an ionised gas.

A point source emitting 628 lumen of luminous flux uniformly in all directions is placed at the origin. Calculate the illuminance on a small area placed at (1.0m, 0, 0) in such a way that the normal to the area makes an angle of 37º with the X-axis.

What is stationary interference? How can we get, the resultant intensity of super position of waves emanated from the incoherent sources?

Give expression for induced emf in AC generator. Discuss, with fogure, how this emf changes with time during one rotation of coil.

For a given light sensitive material and a source of incident radiation of fixed frequency, how does the photoelectric current decay with the intensity of incident light?

The plates of a parallel-plate capacitor are made of circular discs of radii 5.0cm each. If the separation between the plates is 1.0mm, what is the capacitance?

Explaination of experimental results of photoelectric effect with Einstein's equation.

Is it necessary for the plane of the orbit of a satellite to pass through the centre of the earth?

Two babies are born in a moving train, one in the compartment adjacent to the engine and other in the compartment adjacent to the guard. According to the train frame, the babies are born at the same instant of time. Who is elder accordmg to the ground frame?