Physics Test - ...

A conducting circular loop is placed in a uniform magnetic field, \(\mathrm{B}=0.025 \mathrm{~T}\) with its plane perpendicular to the direction of the magnetic field. The radius of the loop is made to shrink at a constant rate of \(1 \mathrm{~mm} \mathrm{~s}^{-1}\). Find the induced emf in the loop when its radius is \(2 \mathrm{~cm}\), is:

A particle of mass \(m\) carrying charge \(+q_{1}\) is revolving around a fixed charge \(-q_{2}\) in a circular path of radius r. Calculate the period of revolution.

A magnetic needle free to rotate in a vertical plane parallel to the magnetic meridian has its north tip pointing down at \(22^{\circ}\) with the horizontal. The horizontal component of the earth's magnetic field at the place is known to be \(0.35 \mathrm{G}\). Determine the magnitude of the earth's magnetic field at the place.

Sound waves cannot travel in:

Satellite going round the earth in a circular orbit loses some energy due to collision. Its speed is \(\mathrm{v}\) and distance from the earth is \(\mathrm{d}\)______.

If a full-wave rectifier circuit is operating from \(50\) Hz mains, then the fundamental frequency in the ripple will be

A permanent retarding force of\(50 \mathrm{~N}\)is applied on a body of mass\(20 \mathrm{~kg}\)moving with an initial speed of\(15 \mathrm{~ms}^{-1}\). How long will it take for the body to stop?

A body is orbiting Earth at a mean radius \(9\) times as great as the orbit of a geostationary satellite. In how many days will it complete one revolution around Earth and what is its angular velocity?

The distance of the planet from the earth is measured by _________.

Which among the following is not related to the conservation of charge?