Friction causes a decrease in kinetic energy, often converted into thermal energy.

The object's kinetic energy increases, and it speeds up.

The object's gravitational potential energy increases.

Elastic potential energy is stored in the spring.

The object's kinetic energy decreases, and it slows down.

Net work done on the object.

Energy: The capacity to do work. | Work: Transfer of energy. | Power: Rate at which work is done or energy is transferred.

Kinetic Energy: Energy of motion, $K = \frac{1}{2}mv^2$. | Potential Energy: Stored energy due to position or condition, e.g., $U = mgh$ or $U = \frac{1}{2}kx^2$.

Conservative Forces: Work done is path-independent (e.g., gravity, spring force). | Non-Conservative Forces: Work done is path-dependent (e.g., friction, air resistance).

The total energy of an isolated system remains constant; energy can change forms but is neither created nor destroyed.

The sum of potential (U) and kinetic (K) energies in a system: $TME = U + K$.

The net work done on an object equals its change in kinetic energy: $W_{net} = \Delta K = K_f - K_i$.

The rate at which work is done or energy is transferred: $P = \frac{W}{t}$ or $P = \frac{\Delta E}{t}$.

Watts (W), equivalent to joules per second (J/s).