List of top Physics Questions

In the following diagram, the work done in moving a point charge from point P to point A, B and C are \( W_A, W_B, W_C \) respectively. Then (A, B, C are points on semicircle and point charge \( q \) is at the centre of semicircle)
 

A block of mass \(m\) is placed in equilibrium on a moving horizontal plank. The maximum horizontal acceleration of the plank for \(\mu = 0.2\) is (Acceleration due to gravity = \(10 \, {ms}^{-2}\)).
A person climbs up a conveyor belt with a constant acceleration. The speed of the belt is \( \sqrt{\frac{g h}{6}} \) and the coefficient of friction is \( \frac{5}{3\sqrt{3}} \). The time taken by the person to reach from A to B with maximum possible acceleration is: \includegraphics[]{87.png}
The ground state energy of hydrogen atom is -13.6 eV. The potential energy of the electron in this state is:
An aircraft executes a horizontal loop of radius 1 km with a speed of 900 kmph. Then, the ratio of its centripetal acceleration to the acceleration due to gravity is:
The average power generated by a 90 kg mountain climber who climbs a summit of height 600 m in 90 minutes is (Acceleration due to gravity \( g = 10 \) m/s\(^2\)):
In case of diffraction, if \( a \) is a slit width and \( \lambda \) is the wavelength of the incident light, then the required condition for diffraction to take place is:

Two condensers \( C_1 \) & \( C_2 \) in a circuit are joined as shown in the figure. The potential of point A is \( V_1 \) and that of point B is \( V_2 \). The potential at point D will be:

The Poisson’s ratio of a material is 0.4. If the force is applied to a wire of this material, there is a decrease of cross-sectional area by 2%. The percentage increase in its length is:
If the current through an inductor increases from 2 A to 3 A, the magnetic energy stored in the inductor increases by
If the work done in stretching a wire by 1 mm is 2 J, the work necessary for stretching another wire of same material but with double radius of cross section and half the length by 1 mm is
A very long straight conductor is carrying a steady current of \(2.2 \, {A}\). The conductor is placed on a horizontal table such that the current in the conductor is from south to north. If the horizontal component of the earth's magnetic field at the place is \(3.2 \times 10^{-5} \, {T}\), the force per unit length on the conductor is:
A substance of mass \( m \) requires a power input of \( P \) to remain in the molten state at its melting point. When the power is turned off, the sample completely solidifies in time \( t \). The latent heat of the substance is

In a Carnot engine, the absolute temperature of the source is 25% more than the absolute temperature of the sink. The efficiency of the engine is

One mole of a gas having \( \gamma = \frac{7}{5} \) is mixed with one mole of a gas having \( \gamma = \frac{4}{3} \). The value of \( \gamma \) for the mixture is ( \( \gamma \) is the ratio of the specific heats of the gas)

The displacement of a particle executing simple harmonic motion is \( y = A \sin(2\pi t + \phi) \, \text{m} \), where \( t \) is time in seconds and \( \phi \) is the phase angle. At time \( t = 0 \), the displacement and velocity of the particle are 2 m and 4 ms-1. The phase angle, \( \phi \) =

Heat is supplied at constant pressure to a diatomic gas. The part of this heat that was utilized to increase its internal energy is:

If the potential difference across \(PQ\) is 4V, the potential difference across \(A\) and \(B\) in the given figure is:


 

If the frequency of a wave is increased by 25%, then the change in its wavelength is (medium not changed):

In an inelastic collision, after collision the kinetic energy
Two samples of same gas (\(\gamma = \frac{3}{2}\)) have equal volume. If their volumes are doubled by adiabatic and isothermal processes respectively for sample 1 and 2. Their final pressures are now equal. The ratio of initial pressures is:
The length of the side of a cube is \( 1.2 \times 10^{-2} \) m. Its volume up to correct significant figures is:
A solid cylinder rolls down on an inclined plane of height \( h \) and inclination \( \theta \). The speed of the cylinder at the bottom is:
An object is projected upwards from the foot of a tower. The object crosses the top of the tower twice with an interval of 8 s and the object reaches the foot after 16 s. The height of the tower is (Given \( g = 10 \, m/s^2 \))
A light body of momentum \( P_L \) and a heavy body of momentum \( P_H \), both have the same kinetic energy, then: