List of top Physics Questions

A circular coil of mean radius of $7\, cm$ and having $4000$ turns is rotated at the rate of $1800$ revolutions per minute in the earth's magnetic field $(B=0.5$ gauss), the emf induced in coil will be
If the heat of $110\, J$ is added to a gaseous system, whose internal energy is $40\, J$, then the amount of external work done is
Consider a system of two particles having masses $m_1$ and $m_2$. If the particle of mass $m_1$ is pushed towards the mass centre of particles through a distance '$d$', by what distance would be particle of mass $m_2$ move so as to keep the mass centre of particles at the original position ?
A mass of $0.5 \,kg$ moving with a speed of $1.5 \,m/s$ on a horizontal smooth surface, collides with a nearly weightless spring of force constant $k = 50 \,N/m$. The maximum compression of the spring would be
A ray of light is incident on an equilateral glass prism placed on a horizontal table. For minimum deviation which of the following is true ?
If $ \lambda_m $ denotes the wavelength at which the radiative emission from a black body at a temperature $T\, K$ is maximum, then
A resonance air column of length $40\,cm$ resonates with a tuning fork of frequency $450 \,Hz$. Ignoring end correction, the velocity of sound in air will be :
The energy in $MeV$ is released due to transformation of $1\, kg$ mass completely into energy, is $\left(c=3 \times 10^{8} m / s \right)$
A charged particle is suspended in equilibrium in a uniform vertical electric field of intensity $20000\, V / m$. If mass of the particle is $9.6 \times 10^{-16} kg$, the charge on it and excess number of electrons on the-particle respectively are $\left( g =10\, m / s ^{2}\right)$
$20\, kV$ potential is applied across $X$-ray tube, the minimum wavelength of $X$-ray emitted will be
A cord attached to a vibrating tuning fork is divided into six segments under tension of $36 \,N$. It will be divided into fowl segments, if the tension is:
An object travels north with a velocity of $ 10\text{ }m{{s}^{-1}} $ and then speeds up to a velocity of $ 25\text{ }m{{s}^{-1}} $ in 5 s. The acceleration of the object in these 5 s is:
The mass of proton is 1.0073 u and that of neutron is 1.0087 u (u = atomic mass unit). The binding energy of  \(_2^4 He\) is (Given: helium nucleus mass ≈ 4.0015 u) 
In which of the following systems will be radius of the first orbit (n=1) be minimum:
Barrier potential of a p-n junction diode does not depend on:
If a full wave rectifier circuit is operating from 50 Hz mains, the fundamental frequency in the ripple will be:
A n-p-n transistor conducts when
Reverse bias applied to a junction diode
A stationary particle explodes into two particles of masses m1 and m2 which move in opposite directions with velocities v1 and v2. The ratio of their kinetic energies \(\frac{E_1}{E_2}\) is:

A thin circular ring M and radius ‘r’ is rotating about its axis with a constant angular velocity ω. Four objects each of mass m, are kept gently to the opposite ends of two perpendicular diameters of the ring. The angular velocity of the ring will be - 

A solid cylinder of mass M and radius R rolls without slipping down an inclined plane of length L and height h. What is the speed of its centre of mass when the cylinder reaches its bottom-
A ball rolls without slipping. The radius of gyration of the ball about an axis passing through its centre of mass is K. If radius of the ball be R, then the fraction of total energy associated with its rotational energy will be:
When a long spring is stretched by 2 cm, its potential energy is U. If the spring is stretched by 10 cm, the potential energy stored in it will be:
We consider the radiation emitted by the human body. Which of the following statements is true:

Two spheres of masses m and M are situated in the air and the gravitational force between them is F. The space around the masses in now filled with a liquid of specific density 3. The gravitational force will now be: