Work, Energy and Power

Force on a particle moving in straight line is given by $\overrightarrow{F}=6t^2\widehat{i}-3t\widehat{j}$  and velocity is $\overrightarrow{v}=3t\widehat{i}+6t\widehat{j}$ . Find power at t = 2.

If the coefficient of restitution is 0.5, what is the percentage loss of energy on each rebounding of a ball dropped from a height?

The kinetic energy of a body decreases by 36%. The decrease in linear momentum is

A particle of mass m is dropped from rest from a height h₀ on a horizontal floor. The coefficient of restitution between the floor and particle is e. Maximum height attained by the particle after second collision is

The potential energy of a particle varies with x according to the relation U(x) = x² – 4x. The point x = 2 is a point of

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

A body possesses kinetic energy x, moving on a rough horizontal surface, is stopped in a distance y. The friction force exerted on the body is

A small block of mass 10 g is projected along the smooth path from rest as shown in the given figure below. Find its speed at the point B

Two springs with spring constants $k_1=1200N/m$ and $k_2=500N/m$ are stretched by the same force. The ratio of potential energy in the springs will be

A mass of $0.5 kg$ $$ moving with a speed of $1. 5m/s$ $$ on a horizontal smooth surface, collides with a nearly weightless spring of force constant $k=50N/m$ $$ . The maximum compression of the spring would be