YEAR 8 PHYSICAL SCIENCE Energy Student Objectives By

YEAR 8 PHYSICAL SCIENCE Energy

Student Objectives By the end of this lesson most of you will be able to define energy, work, and power.

Energy is the ability to do work and is used in order to perform work. Energy is needed to move or heat something, to make a noise or to change an objects shape. Energy makes things happen.

Work is the name given to the effects of using energy. Whenever an object is shifted or forced to change shape, then work has been done. Work is a force over a distance acting to move or change an object

POWER Power is how fast work is done (or the rate at which work is done)

PUSH DEMO I need two volunteers. . . One volunteer will push against the wall and the other volunteer will push on a chair so that the chair moves at least 1 metre.

1 minute think time. . . Did one or both of these students do any work? Did either of the student use energy? Be prepared to share your ideas

DISCUSSION Did one or both of these students do any work? The one pushing on the chair did work; the other pushing against the wall did not. “Work” requires that an object be moved. Did either of the students use energy? Yes – energy contributes to doing work, but not all energy successfully does work.