Physics

Consider a process on a system shown in figure below. During the process, the work done by the system

A rain drop of radius r falls in air with terminal velocity v. What is the terminal velocity of a rain drop of radius 3r?

Two circular rings (of same material) are of same thickness. The diameter of first ring is twice that of second. The moment of inertia of first ring as compared to that of second is

In rotational motion of a rigid body about an axis, particles move with

A body of moment of inertia 4 kg m² rotating with an angular speed of 4 rad/s has the 4x J of kinetic energy. Determine the value of x.

An insect of mass m = 2 g is inside a vertical drum of radius 1 m that is rotating with an angular velocity of 10 rad/s. If the insect does not fall off then the minimum coefficient of friction is

The position x of a particle of mass 2 kg moving along straight line is given as x = (t – 2)2, where t is in second and x is in metre. The work done by the force in first 2 s is

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

What will happen without this theory of bohr's second postulate?

If length of stretched string is increased by 50% keeping mass per unit length same, then in order to keep its frequency of vibration constant, its tension must be increased by