Question Bank Directory

A short electric dipole has a dipole moment of $16 \times 10^{-9} C m$. The electric potential due to the dipole at a point at a distance of $0.6 m$ from the centre of the dipole, situated on a line making an angle of $60^{\circ}$ with the dipole axis is : ($\frac{1}{4\pi \epsilon_0} = 9 \times 10^9 N m^2/C^2$)

Dimensions of stress are :

An iron rod of susceptibility 599 is subjected to a magnetising field of $1200 A m^{-1}$. The permeability of the material of the rod is : ($\mu_0 = 4\pi \times 10^{-7} T m A^{-1}$)

A spring is stretched by 5 cm by a force 10 N. The time period of the oscillations when a mass of 2 kg is suspended by it is

The quantities of heat required to raise the temperature of two solid copper spheres of radii $r_1$ and $r_2$ ($r_1 = 1.5 r_2$) through 1 K are in the ratio :

A screw gauge gives the following readings when used to measure the diameter of a wire. Main scale reading : 0 mm. Circular scale reading : 52 divisions. Given that 1 mm on main scale corresponds to 100 divisions on the circular scale. The diameter of the wire from the above data is

A small block slides down on a smooth inclined plane, starting from rest at time $t = 0$. Let $S_n$ be the distance travelled by the block in the interval $t = n - 1$ to $t = n$. Then, the ratio $\frac{S_n}{S_{n+1}}$ is

A capillary tube of radius r is immersed in water and water rises in it to a height h. The mass of the water in the capillary is 5 g. Another capillary tube of radius 2r is immersed in water. The mass of water that will rise in this tube is :

The mean free path for a gas, with molecular diameter d and number density n can be expressed as :

A series LCR circuit is connected to an ac voltage source. When L is removed from the circuit, the phase difference between current and voltage is $\frac{\pi}{3}$. If instead C is removed from the circuit, the phase difference is again $\frac{\pi}{3}$ between current and voltage. The power factor of the circuit is :

The capacitance of a parallel plate capacitor with air as medium is $6 \mu F$. With the introduction of a dielectric medium, the capacitance becomes $30 \mu F$. The permittivity of the medium is : ($\epsilon_0 = 8.85 \times 10^{-12} C^2 N^{-1} m^{-2}$)

The phase difference between displacement and acceleration of a particle in a simple harmonic motion is :

In Young's double slit experiment, if the separation between coherent sources is halved and the distance of the screen from the coherent sources is doubled, then the fringe width becomes :

For the logic circuit shown, the truth table is:

Which of the following graph represents the variation of resistivity ($\rho$) with temperature (T) for copper?

Two bodies of mass $4\text{ kg}$ and $6\text{ kg}$ are tied to the ends of a massless string. The string passes over a pulley which is frictionless (see figure). The acceleration of the system in terms of acceleration due to gravity (g) is :

A charged particle having drift velocity of $7.5 \times 10^{-4} \text{ m s}^{-1}$ in an electric field of $3 \times 10^{-10} \text{ Vm}^{-1}$, has a mobility in $\text{m}^2 \text{ V}^{-1} \text{ s}^{-1}$ of :

For a plane electromagnetic wave propagating in $x$-direction, which one of the following combination gives the correct possible directions for electric field ($E$) and magnetic field ($B$) respectively?

The velocity of a small ball of mass $M$ and density $d$, when dropped in a container filled with glycerine becomes constant after some time. If the density of glycerine is $\frac{d}{2}$, then the viscous force acting on the ball will be

The electron concentration in an $n$-type semiconductor is the same as hole concentration in a $p$-type semiconductor. An external field (electric) is applied across each of them. Compare the currents in them.