List of top Physics Questions

The waves used for line-of-sight $(LOS)$ communication is
The ratio of the energy required to raise a satellite upto a height $h$ above the earth of radius $R$ to that the kinetic energy of the satellite into that orbit is
The power of biconvex lens is 10 dioptre and the radius of curvature of each surface is 10 cm. Then the refractive index of the material of the lens is
The dimensional formula for electric flux is
Sodium in sodium vapour lamp produces
In an isothermal process, there is
If a planet has twice the mass of earth and three times the radius $(R)$ of earth, then the escape velocity of the planet is ($\upsilon_e$ = escape velocity of earth)
A tank full of water has a small hole at its bottom. If one-fourth of the tank is emptied in $t_1$ seconds and the remaining three fourths of the tank is emptied is $t_2$ seconds, then ratio $(t_1/t_2)$ is
A stone tied at the end of a string 80 cm long is whirled in a horizontal circle with a constant speed. If the stone makes 25 revolutions in 14 s, what is the magnitude of acceleration of the stone ?
A real gas behaves as an ideal gas,
A piece of brass (alloy of copper and zinc) weighs 12.9 g in air. When completely immersed in water it weighs 11.3 g. What is the mass of copper contained in the alloy ? (Specific gravities of copper and zinc are 8.9 and 7.1 respectively)
A particle is moving on a circular path of 10 m radius. At any instant of time, its speed is ${5\, m \, s^{-1}}$ and the speed is increasing at a rate of ${2\, m \, s^{-2}}$. The magnitude of net acceleration at this instant is
A galvanometer can be converted into a voltmeter by connecting a
A closed organ pipe and an open organ pipe of same length produce $2 \,beats/second$ when they are set into vibrations together in fundamental mode. The length of open pipe is now halved and that of closed pipe is doubled. The number of beats produced will be
A circular coil of $n$ turns and radius $R$ has a magnetic induction of strength at its centre is
A ball of mass $m$ moving with a constant velocity $u$ strikes against a ball of same mass at rest. If $e$ = coefficient of restitution, then what will be the ratio of velocity of two balls after collision ?
An object is kept on a smooth inclined plane of $1 $ in $ l. $ The horizontal acceleration to be imparted to the inclined plane so that the object is stationary relative to incline is
Rydberg constant is
An electromagnetic wave transfers
Which of the following wave can?t travel in vacuum?
What is the name given to that part of the electromagnetic spectrum which is used for taking photographs of earth under foggy conditions from great heights?
A soap bubble exhibits brilliants colours due to
The gas cause Green House Effect is
The average degree of freedom per molecule for a gas is $6$. The gas performs $25\,J$ of work when it expands at constant pressure. The heat absorbed by the gas is
The maximum kinetic energy of the photoelectrons depends only on