When do we say that work is done?

1. Definition of Work:
– Work in physics is related to the transfer of energy when something moves because of a force.
– When a force causes an object to move in the same direction as the force, work is said to be done.

2. Work Equation:
– The formula for work is:
Work = Force x Distance x cos(θ)
– Work happens when a force is applied, and the object moves in the direction of that force.

3. Conditions for Work:
– Work is done when the force applied causes displacement (movement) in the direction of the force.
– If there’s no movement despite applying force or if the force applied is at a right angle to the direction of movement, no work is done.

4. Examples:
– Pushing a box across the floor: Work is done because the force applied makes the box move in the direction of the push.
– Pushing a box sideways or upwards: If the box moves sideways while you push it upwards, no work is done because the force and movement aren’t in the same direction.

5. Summary:
– Work is done when a force causes something to move in the direction of that force. If the force and movement are in the same direction, then work happens.