Chapter 3: Work, Energy, Power & System of Particles (Set-2)

Work done by a constant force is calculated using:

A body does zero work when:

If kinetic energy of a body becomes 4 times, speed becomes:

Work done on a body reduces if:

On doubling both mass and velocity, KE becomes:

If net work is positive, then the body:

When force is opposite displacement, θ =

Work done by centripetal force is:

Average power is defined as:

Instantaneous power equals:

A key property of conservative forces is:

Which is ALWAYS non-conservative?

Conservative forces:

Work done by gravity during descent:

A force whose work depends on path followed is:

In a closed loop, work done by friction is:

Which force conserves mechanical energy?

Potential energy decreases when:

COM of a system depends on:

COM for two equal masses lies:

The motion of COM is governed by:

For a system free of external forces, COM:

In explosion of a stationary bomb, COM:

Can COM lie outside the body?

COM moves as if:

For a system of particles, total momentum equals:

Momentum is conserved when:

The unit of impulse is equal to:

When a constant force acts for a time t, momentum changes by:

A perfectly inelastic collision is one in which:

Momentum is:

Two equal masses collide elastically and exchange velocities. This follows conservation of:

A bullet strikes and embeds into a block. This is:

Change in momentum per unit time is:

Total mechanical energy =

Mechanical energy conserved when:

PE of a raised body is due to:

When a body falls freely, PE:

In absence of dissipative forces, mechanical energy:

A compressed spring stores:

A 10 N force moves object 5 m. Work =

If velocity becomes 3 times, KE becomes:

A 2 kg mass moving at 4 m/s has momentum:

A force perpendicular to velocity does:

If work done is negative, KE:

In a free fall, work done by gravity is:

Power becomes zero when:

Units of KE and work are:

Work done by internal forces of a system affects:

Impulse is equal to: