List of top Physics Questions

A circular coil of area \(3 \times 10^{-2} \text{ m}^2\), 900 turns and a resistance of 1.8 Ω is placed with its plane perpendicular to a uniform magnetic field of \(3.5 \times 10^{-5}\) T. The current induced in the coil when it is rotated through 180° in half a second is
The length of a potentiometer wire is 2.5 m and its resistance is 8 Ω. A cell of negligible internal resistance and emf of 2.5 V is connected in series with a resistance of 242 Ω in the primary circuit. The potential difference between two points separated by a distance of 20 cm on the potentiometer wire is
The magnetic field due to a current carrying circular coil on its axis at a distance of \(\sqrt{2} d\) from the centre of the coil is B. If d is the diameter of the coil, then the magnetic field at the centre of the coil is
The potential difference between points C and D of the electrical circuit shown in the figure is
The magnetic field at a point P on the axis of a short bar magnet of magnetic moment M is B. If another short bar magnet of magnetic moment 2M is placed on the first magnet such that their axes are perpendicular and their centres coincide. The resultant magnetic field at the point P due to both the magnets is
A square coil of side 10 cm having 200 turns is placed in a uniform magnetic field of 2 T such that the plane of the coil is in the direction of magnetic field. If the current through the coil is 3 mA, then the torque acting on the coil is
If a particle of mass 10 mg and charge 2 µC at rest is subjected to a uniform electric field of potential difference 160 V, then the velocity acquired by the particle is
Four electric charges 2 µC, Q, 4 µC and 12 µC are placed on x-axis at distances x = 0, 1 cm, 2 cm and 4 cm respectively. If the net force acting on the charge at origin is zero, then Q =
In Young's double slit experiment, if the distance between 5th bright and 7th dark fringes is 3 mm, then the distance between 5th dark and 7th bright fringes is
If \(W_1\) is the work done in increasing the radius of a soap bubble from 'r' to '2r' and \(W_2\) is the work done in increasing the radius of the soap bubble from '2r' to '3r', then \(W_1: W_2 =\)
Three moles of an ideal gas undergoes a cyclic process ABCA as shown in the figure. The pressure, volume and absolute temperature at points A, B and C are respectively \((P_1, V_1, T_1)\), \((P_2, 3V_1, T_1)\) and \((P_2, V_1, T_2)\). Then the total work done in the cycle ABCA is (R- Universal gas constant).
To increase the length of a metal rod by 0.4%, the temperature of the rod is to be increased by (Coefficient of linear expansion of the metal = \(20 \times 10^{-6}\) °C⁻¹)
An air bubble rises from the bottom to the top of a water tank in which the temperature of the water is uniform. The surface area of the bubble at the top of the tank is 125% more than its surface area at the bottom of the tank. If the atmospheric pressure is equal to the pressure of 10 m water column, then the depth of water in the tank is
An air bubble rises from the bottom to the top of a water tank in which the temperature of the water is uniform. The surface area of the bubble at the top of the tank is 125% more than its surface area at the bottom of the tank. If the atmospheric pressure is equal to the pressure of 10 m water column, then the depth of water in the tank is
The power of a refrigerator that can make 15 kg of ice at 0 °C from water at 30 °C in one hour is
The pressure of a mixture of 64 g of oxygen, 28 g of nitrogen and 132 g of carbon dioxide gases in a closed vessel is P. Under isothermal conditions if entire oxygen is removed from the vessel, the pressure of the mixture of remaining two gases is
A body of mass 'm' moving with a velocity of 'v' collides head on with another body of mass '2m' at rest. If the coefficient of restitution between the two bodies is 'e', then the ratio of the velocities of the two bodies after collision is
A thin uniform circular disc of mass \(\frac{10}{\pi^2}\) kg and radius 2 m is rotating about an axis passing through its centre and perpendicular to its plane. The work done to increase the angular speed of the disc from 90 rev/min to 120 rev/min is
A force separately produces accelerations of 18 ms⁻², 9 ms⁻² and 6 ms⁻² in three bodies of masses P, Q and R respectively. If the same force is applied on a body of mass P+Q+R, then the acceleration of that body is
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
If the amplitude of a damped harmonic oscillator becomes half of its initial amplitude in a time of 10 s, then the time taken for the mechanical energy of the oscillator to become half of its initial mechanical energy is
If the length of a rod is measured as 830600 mm, then the number of significant figures in the measurement is
The phenomenon of physics that deals with the constitution and structure of matter at the minute scales of atoms and nuclei is
If a body projected with a velocity of 19.6 ms⁻¹ reaches a maximum height of 9.8 m, then the range of the projectile is (Neglect air resistance)
A particle initially at rest is moving along a straight line with an acceleration of 2 ms⁻². At a time of 3 s after the beginning of motion, the direction of acceleration is reversed. The time from the beginning of the motion in which the particle returns to its initial position is