Motion, Forces, Machines (Unit 4)

Machines will not reduce the amount of _____________ that has to be done.

• effort force

• resistance force

• work

• friction

A _____________ pulley will change the direction of movement, but not the force.

• fixed

• moveable

• block and tackle

• double

If the resistance force is increased and the effort force is decreased, the mechanical advantage will _____________

• increase

• decrease

• remain the same

A lever's input arm is 10m long and the output arm is 2m long, the MA is _____________.

• .20

• 5

• 20

• 200

Tommy does 15J of work to push the pencil over 1m. How much force did he use?

• 0.15N

• 15N

• 16N

• 14N

Angela uses a force of 25N to lift her grocery bags while doing 50J of work. How far did she lift the grocery bags?

• 0.5m

• 2m

• 75m

• 1250m

Who does more work? You, lifting a 600N box up one meter, or your friend using a 5m ramp to move the box up 1 meter?

• You

• Your Friend

• The work is the same, your friend used less force over a greater distance

What happens to your effort force when you move the fulcrum closer to the load?

• it increases

• it decreases

• it depends on how large the load is

• it depends on how long the lever is

A moveable pulley has a MA of _________

• 0.5

• 1

• 2

• 3

What does a mechanical advantage of 10 mean?

• That you have to use 10x more force, because the machine divides your force by 10.

• That your object will move 10x farther, because the machine divides your force by 10.

• That you can use 1/10 as much force, because the machine multiples your force by 10