Work Done by Friction in Different Cases

Work Done by Friction in Different Cases

### Formula

$$W_f=-\mu Ns$$

### Terminologies

- Wf → Work done by friction.

- μ → Coefficient of friction.

- N → Normal force.

- s → Displacement.

### Conditions / Special Cases

For horizontal surface:

$$N=mg$$

Therefore:

$$W_f=-\mu mgs$$

### Usage

- Used in energy loss due to friction problems.