List of practice Questions

A convex lens of focal length 40 cm and a concave lens of focal length 20 cm are in contact. The power of their combination in dioptre is
The reason for the phenomenon of interference is
Which is used to produce polarised light?
A charge 'q' placed at the centre on the line joining two charges 'Q' will be in equilibrium if 'q' will be equal to
What is the angle between the electric dipole moment \(\vec{p}\) and the electric field strength \(\vec{E}\) when the dipole is in a stable equilibrium?
Which of the following physical quantities is a vector?
The value of maximum amplitude produced due to interference of two waves given by \(Y_1 = 4\sin(\omega t)\) and \(Y_2 = 3\cos(\omega t)\) is
The formula for magnetic energy density for a solenoid is
LASER action needs
Light is a transverse wave because it shows
The half-life of a radioactive isotope (\(^{210}\)Bi) is 5 days. The fraction of the nuclei undecayed at the end of 20 days will be
The ratio of electric force and gravitational force acting between two charges is in the order of
The phase difference between electric wave and magnetic wave in the electromagnetic wave is
When the distance between source of light and screen is increased, then fringe width
The unit of radioactivity is
Which of the following has the highest penetrating power?
Which range of frequency is used in TV transmission?
The dispersive power of a prism depends on
Three capacitors of capacitance 6 µF are available. The minimum and maximum capacitances obtained are
The root mean square (r.m.s) value of alternating current equation I = 60 sin 100 πt is
The impedance of L-R circuit is
The radius of a circular current loop is made double and the current is made half. The magnetic moment of the loop will become
The self-inductance of a choke coil is 5 henry. The current through it is increasing at a rate of 2 AS\(^{-1}\). The self-induced emf in the choke coil will be
Magnetic moment of the earth is
Nickel is