What machine is this?

• inclined plane

• pulley

• wedge

What machine is this?

• pulley

• screw

• wedge

What machine is this?

• lever

• pulley

• wheel and axle

What machine is this?

• lever

• screw

• pulley

What machine is this?

• lever

• wheel and axle

• screw

What machine is this?

• lever

• screw

• wheel and axle

Is this a type of catapult?

• No

• Yes

What kind of simple machine?

• inclined plane
• lever
• wheel and axle
• pulley

What do simple machines do?

• increase force
• decrease force
• increase work
• decrease work

The boy can lift the barrel or roll the barrel up the inclined plane.  In which does he do more work?

• when lifting the barrel
• when rolling the barrel
• neither- both are the same amount
• neither- no work is done