Browse and search thousands of solved questions for your preparation.
Free questions with full explanations — locked behind signup to protect quality.
The dependence of acceleration due to gravity g on the distance r from the centre of the earth assumed to be a sphere of radius R of uniform density is as shown in the figure below:
A 250-turn rectangular coil with a length of $2.1 \text{ cm}$ and a width of $1.25 \text{ cm}$ carries a current of $85 \text{ }\mu\text{A}$ and is subjected to a magnetic field of strength $0.85 \text{ T}$. What is the work done to rotate the coil by $180^\circ$ against the torque?
Starting from the centre of the earth, having radius R, the variation of g (acceleration due to gravity) is shown by:
The unit of Stefan's constant σ is:
A short bar magnet of magnetic moment $0.4 \text{ J T}^{-1}$ is placed in a uniform magnetic field of $0.16 \text{ T}$. The magnet is in stable equilibrium when the potential energy is:
The following figures show the arrangement of bar magnets in different configurations. Each magnet has a magnetic dipole moment. Which configuration has the highest net magnetic dipole moment?
The $x$ and $y$ coordinates of the particle at any time are $x = 5t - 2t^2$ and $y = 10t$ respectively, where $x$ and $y$ are in metres and $t$ is in seconds. The acceleration of the particle at $t = 2$ s is:
A bar magnet of length L and magnetic dipole moment M is bent in the form of an arc as shown in figure. The new magnetic dipole moment will be:
One mole of an ideal monatomic gas undergoes a process described by the equation $PV^3 = \text{constant}$. The heat capacity of the gas during this process is:
The volume occupied by the molecules contained in $4.5 \text{ kg}$ water at STP, if the molecular forces vanish away, is:
The temperature of a gas is $-50^\circ\text{C}$. To what temperature the gas should be heated so that the RMS speed is increased by 3 times?
A monoatomic gas at a pressure $p$, having a volume $V$ expands isothermally to a volume $2V$ and then adiabatically to a volume $16V$. The final pressure of the gas is: (take $\gamma = 5/3$)
Nickel shows the ferromagnetic property at room temperature. If the temperature is increased beyond Curie's temperature, then it will show:
In the given figure, $a=15 \text{ m/s}^2$ represents the total acceleration of a particle moving in the clockwise direction in a circle of radius $R=2.5 \text{ m}$ at a given instant of time. The speed of the particle is:
Two small spherical metal balls, having equal masses, are made from materials of densities $\rho_1$ and $\rho_2$ such that $\rho_1 = 8\rho_2$ and having radii of $1 \text{ mm}$ and $2 \text{ mm}$, respectively. They are made to fall vertically (from rest) in a viscous medium whose coefficient of viscosity equals $\eta$ and whose density is $0.1\rho_2$. The ratio of their terminal velocities would be:
Two wires are made of the same material and have the same volume. The first wire has a cross-sectional area $A$ and the second wire has a cross-sectional area $3A$. If the length of the first wire is increased by $\Delta l$ on applying a force $F$, how much force is needed to stretch the second wire by the same amount?
A particle moves along a straight line OX. At a time t (in seconds), the displacement x (in metres) of the particle from O is given by x = 40 + 12t - t³. How long would the particle travel before coming to rest?
The terminal velocity of a copper ball of radius $5 \text{ mm}$ falling through a tank of oil at room temperature is $10 \text{ cm s}^{-1}$. If the viscosity of oil at room temperature is $0.9 \text{ kg m}^{-1} \text{ s}^{-1}$, the viscous drag force is:
The horizontal range and the maximum height of a projectile are equal. The angle of projection of the projectile is:
Let a wire be suspended from the ceiling (rigid support) and stretched by a weight $W$ attached at its free end. The longitudinal stress at any point of the cross-sectional area $A$ of the wire is: