What is Work?

Chapter 12- Work and Machines

Section 1: What is Work?

The meaning of Work

• The word work has a different meaning in science then it does in everyday life.

• In science, WORK is when you exert a force that makes an object move in the same direction as the force.

The meaning of Work

• Work always makes an object move. If you push on a wall the wall does not move.

• Even though you have exerted a force, there is not work done on the wall.

The Meaning of Work

• The motion of the work must be the same directions as the force.

• If you carry books to school, the force you exert is upward.

• The motion of the books is toward school, so no work is done on the books.

On the next three questions, decide weather there is work or no work.

Multiple Choice

1.) You lift a box of newspapers.

• Work

• No Work

Multiple Choice

2) You hold a heavy piece of wood in one place.

• Work

• No Work

Multiple Choice

3.) You pull your books out of your book bag.

• Work

• No Work

Fill in the Blank

4) Work always makes an object _______________.

Word Bank: ~Move ~ Force ~ Work

Fill in the Blank

5) For work to be done, the object's motion must be in the same directions as the _____________________.

Word Bank: ~Move ~ Force ~ Work