Science 4, Energy and Work

Friction is beneficial because it ___________.

• helps a farmer's seeds fall onto the soil

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

• pulls your bicycle wheels toward the earth's center

a change in position is ________

• motion

• work

• gravity

measured by how much force it takes to move an object

and how far the object moves

• energy

• gravity

• work

• friction

Two students are asked to push 2 boxes of equipment to the closet.

The boxes are the same size.

One box holds 8 basketballs. The other has 2 basketballs.

Why will the student pushing the box of 8 basketballs do more work?

• the 8 basketballs have more weight, and more weight requires greater force to move the box

• the 8 basketballs have less weight, and less weight requires less force to move the box

• the 2 basketballs have less weight, and less weight requires greater force to move the box

Tags

NGSS.MS-PS2-2

Billy Bob ran into the outfield to catch the baseball. Did Billy Bob do any work?

• No, because playing baseball is fun.

• No, because the ball was caught by another player.

• Yes, because he moved over a distance.

A bar that turns on a point is called ___________________.

• a wedge

• an inclined plane

• a lever

A wheelbarrow and a rake are examples of ________.

• an inclined plane

• a lever

• a pulley

When the wheel of a wheel and axle turns one time, the wheel ___________.

• travels a shorter distance than the axles does

• travels a greater distance than the axle does

• does not travel at all

The axle in a wheel and axle turns with greater force than the wheel does,

and the axle moves _______.

• greater distance

• less distance

• the same distance

Tags

NGSS.MS-PS2-1

NGSS.MS-PS2-2

A simple machine made of a wheel with a groove that holds a rope is _____.

• an inclined plane

• a wedge

• a pulley