List of top Physics Questions

The momentum of a photon is $p$. The frequency associated with it is given by
Two conductors have the same resistance at 0°C but the temperature coefficients of resistance are $\alpha_1$ and $\alpha_2$. The respective temperature coefficients of their series and parallel combinations are nearly
Consider a rotating spherical planet. The velocity of a point on its equator is $v$. The effect of rotation of the planet is to make $g$ at the equator $1/2$ of $g$ at the pole. What is the escape velocity for a polar particle on the planet expressed as a multiple of $v$?
Two identical wires A and B have the same length $L$ and carry the same current $I$. Wire A is bent into a circle of radius $R$ and wire B is bent to form a square of side $a$. If $B_1$ and $B_2$ are the values of magnetic induction at the centre of the square respectively, then the ratio $\frac{B_1{B_2}$ is}
A transformer having efficiency of 90% is working on 200 V and 3 kW power supply. If the current in the secondary coil is 6 A the voltage across the secondary coil and the current in the primary coil respectively are
A ray of unpolarised light is incident on a glass plate at the polarising angle of $57^\circ$.
A drop of liquid of density $\rho$ is floating half-immersed in a liquid of density $d$. If $\sigma$ is the surface tension, then the diameter of the drop of the liquid is
When a satellite is on the surface of a planet, it experiences a gravitational force $W$. What is the gravitational force when the satellite is at height $R/50$, where $R$ is the radius of the planet?
A pendulum with a period of 2 seconds at sea level has its length doubled. Its new period is now most nearly:
Two charged spheres are separated by 2 mm. Which of the following would yield the greatest attractive force?
The time-period of a charged particle undergoing a circular motion in a uniform magnetic field is independent of its
A train accelerates from rest at a constant rate $\alpha$ for distance $X_1$ and time $t_1$. After that it retards to rest at constant rate $\beta$ for distance $X_2$ and time $t_2$. Then, it is found that
A smooth inclined plane of length $L$ having inclination $\theta$ with the horizontal inside a lift which is moving down with retardation $\alpha$. The time taken by a body to slide down the inclined plane, from rest, will be:
An ideal fluid with pressure $p$ flows through a horizontal pipe with radius $r$. If the radius of the pipe is increased by a factor of 2, which of the following most likely gives the new pressure?
The chemical potential energy in gasoline is converted to kinetic energy in cars. If a car accelerates from zero to 60 km/h, compared to the energy necessary to increase the velocity of the car from 30 to 60 km/h, the energy necessary to increase the velocity of the car from 30 to 60 km/h is:
Resistors $R_1$ and $R_2$ are placed in parallel as shown. If they have values of $5 \, \Omega$ and $10 \, \Omega$ respectively, their combined equivalent resistance is:
Resistors R1 and R2 are placed in parallel
Average energy in one time period of a simple harmonic oscillator whose amplitude is A, angular velocity $\omega$ and mass m, is:
Which of the following gives the percent change to the Young's modulus for a substance, when its cross-sectional area is increased by a factor of 3?
An air bubble starts rising from the bottom of a lake. Its diameter is 3.6 mm at the bottom and 4 mm at the surface. The depth of the lake is 250 cm and the temperature at surface is 40°C. What is the temperature at the bottom of the lake? Given atmospheric pressure = 76 cm of Hg and $g = 980 \, \text{cm/s^2$}
If a guitar string is 0.5 m long, what is the wavelength of its third harmonic?
When a piece of metal is illuminated by a monochromatic light of wavelength $\lambda$, then stopping potential is $3V_s$. When the same surface is illuminated by light of wavelength $2\lambda$, then stopping potential becomes $V_s$. The value of threshold wavelength for photoelectric emission will be:
Two singly ionised isotopes, X and Y of the same element move at the same speed perpendicular to a uniform magnetic field. Isotope X follows a path of radius 3.43 cm while isotope Y moves along a path 3.35 cm in radius. What is the ratio of the two isotope masses, \( m_Y / m_X \)?
The resistors in the circuits below each represent a light bulb. If all three circuits use the same size battery, which circuit will produce the most light?
The resistors in the circuits
Different objects at different distances are seen by the eye. The parameter that remains constant is
The period of oscillation of a simple pendulum of length \( l \) suspended from the roof of a vehicle which moves down without friction on an inclined plane of inclination \( \theta \), is given by