Let's See What We Know!

What does this picture represent? (show)

• A wedge

• A pulley

• A lever

• A wheel and axle (gear)

What are 2 types of pulleys? PICK 2!

• Spur pulley

• Fixed pulley

• Puppies pullies

• Moveable pulley

A pulley is an example of a

• simple machine

• super complex machine

• horse

• gear train

Which simple machine has a greater mechanical advantage?

(What kind of pulley makes work way easier for us)

• Fixed Pulley

• Moveable Pulley

• I don't know

Answer explanation

Moveable pulleys have a greater mechanical advantage.

In our experiment to lift a load of 1N, it took the FIXED pulley almost 1 Newton (0.9N).

The moveable pulley moved the load with only 0.5 Newtons ---- ( HALF THE WORK! )

A combination of a fixed and moveable pulley is called a

• block the offense

• block and tackle OR compound pulley

• block of cheese

• block the haters

Answer explanation

A block and tackle is when the pulleys are hooked together.

A compound pulley does not attach them.

Both use FIXED and MOVEABLE pulleys!

True or False: Two meshed gears always rotate in opposite directions

(ex. one going clockwise, one counterclockwise)

• True

• False

Answer explanation

Yes! Gears always spin the opposite direction as the spur gears beside them in the gear train.

Select the true answers.

Which are the benefits of gears?

• Can change the plane of rotation

• Can increase or decrease speed

• Can increase or decrease force

• Can make movement happen with less slipping because of the teeth

A large driver gear turning a smaller idler gear is called gearing up.

• The smaller gear increases speed as it rotates more quickly

• The smaller gear increases force as it rotates more slowly

Answer explanation

Great work!

Pictured here are _____ gears.

Select 2 answers.

• Worm gears

• Rack and Pinion gears

• Bevel gears

• Spur gears