List of top Physics Questions

When a wire made of material with Young's modulus Y is subjected to a stress S, the elastic potential energy per unit volume stored in the wire is
If the wavelengths of maximum intensity of radiation emitted by two black bodies A and B are \( 0.5 \, \mu\text{m} \) and \( 0.1 \, \text{mm} \) respectively, then ratio of the temperatures of the bodies A and B is
A Carnot engine A working between temperatures 600 K and T (T \(<\) 600 K) and another Carnot engine B working between temperatures T (T \(>\) 400 K) and 400 K are connected in series. If the work done by both the engines is same, then T =
When an ideal diatomic gas is heated at constant pressure, the fraction of the heat utilised to increase the internal energy of the gas is
A solid sphere of mass 4 kg and radius 28 cm is on an inclined plane. If the acceleration of the sphere when it rolls down without sliding is \( 3.5 \, \text{m s}^{-2} \), then the acceleration of the sphere when it slides down without rolling is
If the maximum velocity and maximum acceleration of a particle executing simple harmonic motion are respectively \( 5 \, \text{m s}^{-1} \) and \( 10 \, \text{m s}^{-2} \), then the time period of oscillation of the particle is
A crane of efficiency 80% is used to lift 8000 kg of coal from a mine of depth 108 m. If the time taken by the crane to lift the coal is one hour, then the power of the crane (in kW) is (Acceleration due to gravity \( = 10 \, \text{m s}^{-2} \))
Two satellites A and B are revolving around the earth in orbits of heights \(1.25R_E\) and \(19.25R_E\) from the surface of earth respectively, where \(R_E\) is the radius of the earth. The ratio of the orbital speeds of the satellites A and B is
Three blocks A, B and C are arranged as shown in the figure such that the distance between two successive blocks is 10 m. Block A is displaced towards block B by 2 m and block C is displaced towards block B by 3 m. The distance through which the block B should be moved so that the centre of mass of the system does not change is
Three blocks A, B and C are arranged as shown in the figure
A body of mass 1 kg is suspended from a spring of force constant \( 600 \, \text{N m}^{-1} \). Another body of mass 0.5 kg moving vertically upwards hits the suspended body with a velocity of \( 3 \, \text{m s}^{-1} \) and embedded in it. The amplitude of motion is
Two bodies A and B of masses 20 kg and 5 kg respectively are at rest. Due to the action of a force of 40 N separately, if the two bodies acquire equal kinetic energies in times \( t_A \) and \( t_B \) respectively, then \( t_A : t_B = \)
A balloon with mass 'm' is descending vertically with an acceleration 'a' (where a \(<\) g). The mass to be removed from the balloon, so that it starts moving vertically up with an acceleration 'a' is
The height of ceiling in an auditorium is 30 m. A ball is thrown with a speed of \( 30 \, \text{m s}^{-1} \) from the entrance such that it just moves very near to the ceiling without touching it and then it reaches the ground at the end of the auditorium. Then the length of auditorium is [Acceleration due to gravity \( = 10 \, \text{m s}^{-2} \)]
If the displacement 'x' of a body in motion in terms of time 't' is given by \(x = A\sin(\omega t + \theta)\), then the minimum time at which the displacement becomes maximum is
If the magnitude of a vector \( \vec{p} \) is 25 units and its y-component is 7 units, then its x-component is
A conveyor belt is moving horizontally with a velocity of \( 2 \, \text{m s}^{-1} \). If a body of mass 10 kg is kept on it, then the distance travelled by the body before coming to rest is (The coefficient of kinetic friction between the belt and the body is 0.2 and acceleration due to gravity is \( 10 \, \text{m s}^{-2} \))
The number of significant figures in the simplification of \( \frac{0.501}{0.05}(0.312-0.03) \) is
The logic gate equivalent to the circuit shown in the figure is:
The logic gate equivalent
The voltage gain and the current amplification factor of a transistor in common emitter configuration are \( 300 \) and \( 60 \) respectively. If the collector resistance is \( 5 k\Omega \), then the base resistance is:
If the maximum and minimum amplitudes of a modulated wave are \( 25 \) V and \( 5 \) V respectively, then the modulation index is:
The ratio of the orders of the spacings of nuclear energy levels and atomic energy levels is:
If a wheel with 24 metallic spokes each \( 40 \) cm long is rotated with a speed of \( 180 \) rev/min in a plane normal to the horizontal component of Earth's magnetic field, the emf induced between the axle and the rim of the wheel is \( E \). If the number of spokes is made \( 12 \) and the wheel is rotated with a speed of \( 90 \) rev/min in the same field, the induced emf is:
If a resistor of resistance \( 4 \Omega \), a capacitor of capacitive reactance \( 6 \Omega \) and an inductor of inductive reactance \( 9 \Omega \) are connected in series with an AC source, then the impedance of the circuit is:
Of the following, Bohr's atomic model is applicable to:
The ratio of the magnitudes of the electric field and \( 10^8 \) times the magnetic field of a plane electromagnetic wave is: