List of top Physics Questions

If the torque acting on an electric dipole when placed at an angle \(30^{\circ}\) with the direction of a uniform electric field is \(\tau\), then the torque acting on the same dipole when placed in the same field at an angle \(45^{\circ}\) is

Two identical isolated capacitors A and B are charged so that each has a charge of 4C. If a charge of \(-2C\) is added to A and \(+2C\) to B, then the ratio of respective potentials is

A conductor with an air core cavity inside, is charged to attain the surface charge density of \(\sigma\). If E is the magnitude of electric field and V is the potential, then inside the cavity

If a diode is forward biased, then the

A solid cylinder of mass 2 kg, length 40 cm and radius 10 cm is placed in contact with a solid sphere of mass 0.5 kg and radius 10 cm such that the centres of the two bodies lie along the geometrical axis of the cylinder. The distance of the centre of mass of the system of two bodies from the centre of the sphere is

The band gap energy of silicon is

In Young’s double slit experiment performed in air medium, the fringe width observed is 1.4 mm. If the entire arrangement is kept in a liquid medium of refractive index 1.4, then the fringe width (in mm) will be

A convex lens having power \(P\) is cut into two halves perpendicular to the principal axis. Then the power of each piece is

In a plane electromagnetic wave, the magnetic field is given by \(B = 400 \times 10^{-6}\sin[(4.0 \times 10^{-4})(t - x/c)]\). The peak value of electric field (in V m\(^{-1}\)) is

A wire of length 1.2 m carrying a current of 4 A, when placed in a uniform magnetic field 5 T experiences a force of 12 N. Then the angle between the direction of current and magnetic field is

Pick out the INCORRECT statement

Three capacitors each of capacitance \(12\,\mu F\), are connected in series. When this combination is connected to a battery of \(12\,V\), the charge drawn from the battery is

An iron ring is held horizontally and a bar magnet is dropped gently through the ring with its length coinciding with the axis of the ring. The acceleration of the freely falling magnet (\(g\) = acceleration due to gravity) is

When a proton moves in a uniform magnetic field such that its velocity has a component along the direction of magnetic field, its trajectory will be a

An electric cell does 10 J of work in carrying a charge of 5 C around a simple closed circuit. The electromotive force of the cell is

A closed organ pipe and an open organ pipe have the same length. The ratio of the frequencies in their third mode of vibrations is

A particle executes linear simple harmonic motion and its potential energy (P.E.), kinetic energy (K.E.), total energy (T.E.) are measured as functions of displacement \(x\) from the mean position at the origin. Then

The temperature at which the r.m.s. velocity of oxygen molecule is equal to that of hydrogen molecule at 20 K is

A point charge \(-q\) is placed at a distance \(x\) from an isolated conducting plane. The electric field at any point \(P\) on the other side of the plane is directed

If the value of \(C_p/C_v\) is unity in the equation \(PV^\gamma = \text{constant}\), then the process is

The total pressure \(P\) inside an air bubble of radius \(r\) at a depth \(h\) below the surface of liquid of density \(\rho\) is (T = surface tension of liquid, \(P_0\) = atmospheric pressure)

Work done in a stretched wire is

Pick out the INCORRECT statement from the following

The ratio of radius of gyration of a circular ring to that of a circular disc, each of same mass and same radius about their respective central axes is