Cue Column:

• What does WET state?
• Which work?
• When to use?

Notes:

Statement: The NET work done by ALL forces on a body equals the change in its kinetic energy.

W_net = W_1 + W_2 + ... + W_n = (1/2)mv_f^2 - (1/2)mv_i^2 = delta_KE

Key Points:

1. W_net includes work by ALL forces (gravity, friction, normal, tension, applied, spring)
2. It is a SCALAR equation — no direction complications
3. Works for variable forces, curved paths, any situation
4. Equivalent to Newton's Second Law but often simpler

When to Use:

• When you need to relate speeds at two points
• When forces vary with position
• When you don't care about the path details

Summary: WET converts a vector problem (forces, directions) into a scalar problem (energies). Extremely powerful.