Ch 8 Energy and Work

Friction is beneficial because it ______.

• pulls your scooter wheels toward the earth’s center

• is what keeps a tennis player from slipping and sliding on the court

• helps a farmer’s seeds fall onto the soil

A change in position is _____.

• motion

• work

• gravity

___ is measured by how much force it takes to move an object and how far the object moves.

• energy

• gravity

• work

 A bar that turns on a point is called ____.

• A lever

• 1. A wedge

• An inclined plane

A contact force that resists the movement of objects against each other and keeps people and objects from slipping and sliding is ___.

• 1. energy

• 1. gravity

• friction

In a lever, what is the point that the bar turns on called?

• wheel

• fulcrum

• cylinder

A wheelbarrow and a rake are examples of ____.

• An inclined plane

• A lever

• 1. A pulley

A simple machine that is a wheel with a rod running through it is ____.

• An inclined plane

• 1. A screw

• 1. A wheel and axle

An inclined plane wrapped around a cylinder is a __.

• An inclined plane

• 1. A screw

• 1. A wheel and axle

Tags

NGSS.MS-PS2-1

A simple machine that is made up of one or more inclined planes and is used to force materials apart is a ____.

• pulley

• wedge

• wheel and axle