GIKI Physics MCQs

Near Earth's surface, gravitational potential energy is mgh.
Only changes in potential energy are physically significant.

Work is W=Fd when force and displacement are parallel.
W=20×5 = 100 J.

Power measures how quickly work is done.
Its SI unit is the watt.

The net work on an object changes its kinetic energy.
This relation is valid for the total work of all forces.

Conservative forces transfer energy between kinetic and potential forms.
Nonconservative work changes total mechanical energy.

For conservative forces, work around a closed path is zero.
Gravity and ideal spring force are examples.

Linear momentum is a vector quantity p=mv.
Its direction is the direction of velocity.

Impulse equals force integrated over time.
For constant force, J=FΔt=Δp.

Internal forces cancel in pairs within a system.
With no net external impulse, total momentum remains constant.

Use a=F/m.
A=12/4 = 3 m/s².

Centripetal force is mv²/r.
F=2×36/4 = 18 N.

Centripetal acceleration is v²/r.
A=100/20 = 5 m/s².