List of top Physics Questions

A body of mass $10 \,kg$ is moving with a constant velocity of $10 \,m/s$. When a constant force acts for $4 s$ on it, it moves with a velocity $2 \,m/s$ in the opposite direction. The acceleration produced in it is

A body of mass $M$ is kept on a rough horizontal surface [friction coefficient $=u$). A person is trying to pull the body by applying a horizontal force $F$ but the body is not moving then

A bullet of mass $m$ moving with velocity $v$ strikes a block of mass $M$ at rest and gets embedded into it. The kinetic energy of the composite block will be

A body of mass $0.5 \,kg$ is projected under gravity with a speed of $98 \,m/s$ at an angle of $ 60^{\circ} $ with the horizontal. The change in momentum (in magnitude) of the body is

In the case of horse pulling a cart, the force that causes the horse to move forward is the force that :

In a triode valve, grid is used to control the plate current, because:

In a uniform magnetic field of induction B a wire in the form of semicircle of radius r rotates about the diameter of the circle with angular frequency $?$. The axis of rotation is perpendicular to the field. If the total resistance of the circuit is R the mean power generated per period of rotation is

If on heating liquid through $80^{\circ} C$, the mass expelled is $(1/100)\,th$ of mass still remaining, the coefficient of apparent expansion of liquid is :

If in a diode valve, the plate potential becomes double, then plate current will be:

Bernoulli's principle is based on the law of conservation of

At what depth below the surface of the earth, acceleration due to gravity $g$ will be half its value $1600\,km $ above the surface of the earth?

The driver in a vehicle moving with a constant speed on a straight road is in a non-inertial frame of reference. A reference frame in which Newton?? laws of motion are applicable is non-inertial.

Smaller drops of liquid resist deforming forces better than the larger drops. Excess pressure inside a drop is directly proportional to its surface area.

In $He-Ne$ laser, population inversion takes place between energy levels of neon atoms. Helium atoms have a meta - stable energy level.

An organ pipe closed at one end has fundamental frequency of $1500\, Hz$. The maximum number of overtones generated by this pipe which a normal person can hear is

A wire fixed at the upper end stretches by length by applying a force $F$. The work done in stretching is

A truck travelling due north at $20 \,ms$ turns west and travels with same speed. What is the change in velocity?

The radius of gyration of a hollow spherical shell is $2.5\, J$. If its frequency of rotation is made 10 times, then new kinetic energy will be:

The magnetic field $ \vec{B} $ in a circular coil does not depend on:

A satellite of mass $m$ revolves around the earth of radius $R$ at a height $x$ from its surface. If $g$ is the acceleration due to gravity on the surface of the earth, the orbital speed of the satellite is

The variation of induced emf (e) with time (t) in a coil if a short bar magnet is moved along its axis with a constant velocity is best represented as

In semiconductors at a room temperature

In an intrinsic semiconductor:

In an equilateral triangle $A B C, F_{1}, F_{2}$ and $F_{3}$ are three forces acting along the sides $A B, B C$ and $A C$ as shown in the given figure. What should be the magnitude of $F_{3}$ so that the total torque about $O$ is zero?

At absolute zero temperature, semiconductor behaves as a/an: