Alternating Current — Physics STD 12 Science — Question

What is the magnitude of the torque and also give its direction.

Give the ratio of number of holes and number of conduction electrons in an intrinsic semiconductor.

An NCC parade is going at a uniform speed of 6km/h through a place under a berry tree on which a bird is sitting at a height of 12.1m. At a particular instant the bird drops a berry. Which cadet (give the distance from the tree at the instant) will receive the berry on his uniform?

Answer the following questions:
Magnetic field lines are always nearly normal to the surface of a ferromagnet at every point. (This fact is analogous to the static electric field lines being normal to the surface of a conductor at every point.) Why?

Which orientation of an electric dipole in a uniform electric field would correspond to stable equilibrium?

An electron is not deflected while passing through a uniform magnetic field. What is the direction of magnetic field?

Which waves are possible to be polarized in X-rays, sound waves and radio waves?

Electric lines in households works at 220 V. What is the magnitude of peak value of emf?

The springs shown in the figure are all unstretched in the beginning when a man starts pulling the block. The man exerts a constant force F on the block. Find the amplitude and the frequency of the motion of the block.