List of top Physics Questions

The molar specific heat at constant pressure of an ideal gas is (7/2)R. The ratio of specific heat at constant pressure to that at constant volume is :-

Two particles of equal mass are connected to a rope $AB$ of negligible mass, such that one is at end $A$ and the other dividing the length of the rope in the ratio $ 1:2 $ from $A$. The rope is rotated about end $B$ in a horizontal plane. Ratio of the tensions in the smaller part to the other is (ignore effect of gravity)

A simple pendulum has a length $l$ and the mass of the bob is $m$. The bob is given a charge $q$ coulomb. The pendulum is suspended between the vertical plates of a charged capacitor. If $E$ is electric field strength between the plates, the time period of pendulum is given by

The magnitude of the magnetic force on a charge is zero when

A light ray in travelling between two media as given below. The angle of incidence on the boundary in all the cases is $30^\circ$. ldentify the correct sequence of increasing order of angles of refraction (1) air to water (2) water to glass (3) glass to water (Refractive indices of glass and water are respectively $\frac{3}{2}$ and $\frac{4}{3}$ )

Four particles, each of mass 1 kg are placed at the comers of a square OABC of side 1 m. O is at the origin of the co-ordinate system. OA and OC are aligned along positive X-axis and positive V-axis respectively. The position vector of the centre of mass is (in m):

In two separate collisions, the coefficients of restitutions $ {{e}_{1}} $ and $ {{e}_{2}} $ are in the ratio 3: 1. In the first collision the relative velocity of approach is twice the relative velocity of separation. Then the ratio between the relative velocity of approach and relative velocity of separation in the second collision is:

An electric fan has blades of length 30 cm as measured from the axis of rotation. If the fan is rotating at 1200 rpm, the acceleration of a point on the tip of the blade is about

Two short magnets have equal pole strengths but one is twice as long as the other. The shorter magnet is placed 20 cm in tan A position from the compass needle. The longer magnet must be placed on the other side of the magnetometer for no deflection at a distance equal to

Two sound waves with wavelengths 5.0 m and 5.5. m respectively, each propagate in a gas with velocity 330 m/s. We expect the following number of beats per second :-

A transverse wave propagating along x-axis is represented by $y(x, t)=8.0 \sin(0.5\pi x-4\pi t-\pi/4)$ where x is in metres and t is in seconds. The speed of the wave is :-

An electric dipole of moment $\vec{p}$ is lying along a uniform electric field $\vec{E}$. The work done in rotating the dipole by 90$^{\circ}$ is :-

A rectangular block of mass m and area of cross-section A floats in a liquid of density \(\rho\) . If it is given a small vertical displacement from equilibrium it undergoes oscillation with a time period T. Then :

Two vibrating tuning forks produce waves given $y_1 = 4 \sin 500 \pi t$ and $y_2 = 2 \sin 506 \,\pi t.$ Number of beats produced per minute is

Two cells, having the same e.m.f. are connected in series through an external resistance R. Cells have internal resistances $r_1$ and $r_2\, (r_1 >\, r_2)$ respectively. When the circuit is closed, the potential difference across the first cell is zero. The value of R is :-

What is SI unit of electric field intensity?

You are given n resistors, each of resistance r. They are first combined to get minimum possible resistance, then they are connected to get the maximum possible resistance. The ratio between rrurnmum to maximum resistance is

The radioactivity of a sample is x at time $t_1$ and is y at time $t_2$. If the mean life of the specimen is $\tau$, the number of atoms that have disintegrated in the time interval $(t_2 - t_1)$ is

A block of mass $ 2\,kg $ rests on a horizontal surface. If a horizontal force of $ 5\,N $ is applied on the block the frictional force on, it is $ (\mu _{k}=0.4,\,\mu _{s}=0.5) $

A bar magnet is held at right angles to a uniform magnetic field. The couple acting on the magnet is to be halved by rotating it from this position. The angle of rotation is

Electromagnetic waves can be deflected by

A rectangular vessel when full of water, takes $10$ minutes to be emptied through an orifice in its bottom. How much time will it take to be emptied when half filled with water ?

An unpolarised beam of intensity $I_0$ is incident on a pair of nicols making an angle of $60^\circ$ with each other. The intensity of light emerging from the pair is

A solenoid $1.5\, m$ long and $0.4\, cm$ in diameter possesses $10$ turns per cm length. A current of $5\, A$ flows through it. The magnetic field at the axis inside the solenoid is

If $\lambda_{1}$ and $\lambda_{2}$ are the wavelengths of the first members of the Lyman and Paschen series respectively, then $\lambda_{1}: \lambda_{2}$ is