List of top Physics Questions

A sound wave travels through air with a frequency of 500 Hz and a wavelength of 0.68 m. Calculate the speed of sound in air.
The gravitational potential energy of an object of mass 5 kg at a height of 10 m above the surface of the Earth is:
A convex lens has a focal length of 20 cm. An object is placed 30 cm in front of the lens. What is the image distance from the lens?
A block of mass 5 kg is pulled along a horizontal surface by a force of 20 N at an angle of 30° to the horizontal. If the coefficient of friction between the block and the surface is 0.2 and the acceleration due to gravity is \( 10 \, \text{m/s}^2 \), what is the work done by the applied force in moving the block 10 m?
A copper block of mass 2 kg is heated from 20°C to 100°C. If the specific heat capacity of copper is \( 400 \, \text{J/kg°C} \), how much heat energy is absorbed by the block? (Assume no phase change occurs.)
A circular coil of 50 turns, each of radius 0.1 m, carries a current of 2 A. If the coil is placed in a uniform magnetic field of 0.5 T perpendicular to its plane, what is the magnitude of the torque acting on the coil?
Two point charges \( +4 \, \mu\text{C} \) and \( -2 \, \mu\text{C} \) are separated by a distance of 0.3 m in air. What is the magnitude of the electrostatic force between them?
A simple pendulum of length 1 m is oscillating with a small amplitude. If the acceleration due to gravity is \( 9.8 \, \text{m/s}^2 \), what is the time period of the pendulum?
A ball is thrown vertically upwards with an initial velocity of 20 m/s. If the acceleration due to gravity is \( 10 \, \text{m/s}^2 \), what is the maximum height reached by the ball?
A current of 2 A flows through a conductor with a resistance of 5 \(\Omega\). Calculate the potential difference across the conductor.
A 5 kg block is placed on a horizontal surface. A force of 10 N is applied to the block. The coefficient of friction between the block and the surface is 0.2. Find the acceleration of the block.
The gravitational potential energy of a 2 kg object at a height of 5 m above the surface of the Earth is?
A projectile is fired with an initial velocity of 20 m/s at an angle of 30\(^\circ\) with the horizontal. Calculate the maximum height reached by the projectile.
A force of 10 N is applied to move a body of mass 5 kg over a distance of 3 meters. Find the work done by the force.
A body of mass 10 kg is moving with a speed of 4 m/s. It is brought to rest by a force in 5 seconds. Calculate the work done by the force.
A light ray is passing from air (refractive index \( \mu_1 = 1.0 \)) into water (refractive index \( \mu_2 = 1.33 \)). If the angle of incidence in air is 30°, what is the angle of refraction in water?
With the help of a labelled diagram, explain the principle of working of a moving coil galvanometer. Write the purpose of using (i) radial magnetic field, and (ii) soft iron core, in it.
In a refracting telescope, the focal length of the objective is 50 times the focal length of the eyepiece. When the final image is formed at infinity, the length of the tube is 102 cm. Find the focal lengths of the two lenses.
An electric dipole of dipole moment \( 1.0 \times 10^{-12} \ \text{Cm} \) lies along the x-axis. An electric field of magnitude \( 2.0 \times 10^4 \ \text{NC}^{-1} \) is switched on at an instant in the region. The unit vector along the electric field is \( \frac{\sqrt{3}}{2} \hat{i} + \frac{1}{2} \hat{j} \). The magnitude of the torque acting on the dipole at that instant is:
The distance of an object from the first focal point of a biconvex lens is \( X_1 \) and distance of the image from second focal point is \( X_2 \). The focal length of the lens is:
Two conductors A and B of the same material have their lengths in the ratio 1:2 and radii in the ratio 2:3. If they are connected in parallel across a battery, the ratio \( \frac{v_A}{v_B} \) of the drift velocities of electrons in them will be:
A point object is placed in air at a distance \( \frac{R}{3} \) in front of a convex surface of radius of curvature \( R \), separating air from a medium of refractive index \( n \) (where \( n<4 \)). Find the nature and position of the image formed.
In case (a) above, is Kirchhoff's first rule (junction rule) valid at each plate of the capacitor? Explain.
A metal rod of length 50 cm is held vertically and moved with a velocity in a magnetic field at the place of 0.4 G. The emf induced across the ends of the rod is:
Calculate the value of the current passing through the battery in the given circuit diagram.