List of top Physics Questions

A man fires bullets at two hillocks, one shorter and the other taller. The taller one is behind the smaller one. If the first echo is heard after 6 s and the second echo after 12 s, then the distance between the hillocks is (velocity of sound in air = 330 m/s):
The ratio of the respective rms velocities of the gas molecules of an ideal gas at 327°C and at 627°C is:
In a Carnot engine, the temperature of the sink is 350 K. If the efficiency of the engine is 50%, the temperature of the source should be:
If an ideal gas, in an insulated vessel, is allowed to expand into another similar evacuated vessel through a valve then:
Two gases under the same thermal conditions have the same number of molecules per unit volume. If the respective molecular diameters of the gases are in the ratio 1 : 3, then their respective mean free paths are in the ratio:
For the flow of incompressible liquid through a pipe, the Venturi-meter is used to measure the:
If a planet orbits the Sun in an elliptical orbit, the quantities associated with the planet that remain constant are:
If an ideal engine needs to transmit a torque of 200 Nm to maintain a rotor at a uniform angular speed of 300 rads\(^{-1}\), then the power required for the engine is:
The analogy between linear motion and rotational motion are given. The FALSE one is:
The collision in which the two colliding particles move together after collision is called:
If a body at rest undergoes one dimensional motion with constant acceleration, then the power delivered to it at a time \( t \) is proportional to:
A car moving with a speed \( v \) is stopped at a distance \( d \) by a retarding force \( F \). The force needed to stop the same car moving with the speed \( 3v \) within the same distance is:
Find the TRUE statement of the algebraic operations of scalar and vector quantities.
The dimensional formula of the gravitational constant is \( M^a L^b T^c \), the values of \( a \), \( b \), and \( c \) are respectively:
If the position of the particle is \( \mathbf{r} = 3 \hat{i} + 2 t^2 \hat{j} \), then the magnitude of its velocity at \( t = 5 \) second in \( {ms}^{-1} \) is:
In Young's double slit experiment, intensity of light at a point on the screen where the path difference becomes \( \lambda \) is I. The intensity at a point on the screen where the path difference becomes \( \frac{\lambda}{3} \) is,
An inductor and a resistor are connected in series to an AC source of 10 V. If the potential difference across the inductor is 6 V, then the potential difference across the resistor is
The de Broglie wavelength of a proton is twice the de Broglie wavelength of an alpha particle. The ratio of the kinetic energies of the proton and the alpha particle is:
The magnetic field at the centre of a circular coil having a single turn of the wire carrying current \( I \) is \( B \). The magnetic field at the centre of the same coil with 4 turns carrying the same current is:
Focal length of a convex lens of refractive index 1.5 is 3 cm. When the lens is immersed in water of refractive index \( \frac{4}{3} \), its focal length will be:
If the displacement of a body moving on a horizontal surface is 151.25 cm in a time interval of 2.25 s, then the velocity of the body in the correct number of significant figures in cm s\(^{-1}\) is:
A bullet of 10 g, moving at 250 m/s, penetrates 5 cm into a tree limb before coming to rest. Assuming uniform force being exerted by the tree limb, the magnitude of the force is:
A narrow single slit of width \( d \) is illuminated by white light. If the first minimum for violet light (\( \lambda = 4500 \, {Å} \)) falls at \( \theta = 30^\circ \), the width of the slit \( d \) in microns is (1 micron = \( 10^{-6} \) m):
Electric conduction in a semiconductor is due to:
A block of mass \( M \) is placed on the floor of a lift at the center. The acceleration required for the lift to descend so that the block exerts a force of \( \frac{Mg}{4} \) on the lift floor is: