Physics Test 162

If x, v and a denote the displacement, the velocity and the acceleration of a particle executing simple harmonic motion of time period T, then, which of the following does not change with time?

When a wave travel in a medium, the particle displacement is given by the equation y = a sin 2 (bt– cx) where a, b and c are constants. The maximum particle velocity will be twice the wave velocity if

A solid conducting sphere of radius a has a net positive charge 2Q. A conducting spherical shell of inner radius b and outer radius c is concentric with the solid sphere and has a net charge –Q.The surface charge density on the inner and outer surfaces of the spherical shell will be respectively

If n drops, each charged to a potential V, coalesce to form a single drop. The potential of the big drop will be

Variation of current passing through a conductor as the voltage applied across its ends is varied as shown in the adjoining diagram. If the resistance (R) is determined at the points A, B, C and D, we will find that

A 10 eV electron is circulating in a plane at right angles to a uniform field at magnetic induction The orbital radius of the electron is

Two identical magnetic dipoles of magnetic moments each, placed at a separation of 2 m with their axis perpendicular to each other. The resultant magnetic field at point midway between the dipole is

A metal rod of length l cuts across a uniform magnetic field B with a velocity v. If the resistance of the circuit of which the rod forms a part is r, then the force required to move the rod is

A coil of inductance 300 mH and resistance 2W is connected to a source of voltage 2V. The current reaches half of its steady state value in

An electromagnetic wave in vacuum has the electric and magnetic field rE and rB , which are always perpendicular to each other. The direction of polarization is given by rX and that of wave propagation by r k . Then