Simple Machines Calculations

What is the ideal mechanical advantage of a lever with a resistance arm of 3 m and an effort arm of 12 m?

• 4
• 0.25
• 15
• 0.5

You use a lever to lift a filing cabinet to get a lost key. The input arm is 2 ft and the output arm is 1 ft. What is the MA of the lever?

• 2
• 0.5
• 1
• 0.25

Tags

NGSS.MS-PS2-1

NGSS.MS-PS2-2

You apply a force on a crowbar to open a stuck door. The effort length of the crowbar is 26 cm long and the resistance length is 4 cm. Find the MA of the crowbar

• 0.15
• 7
• 6.5
• 0.5

A worker uses a board that is 4 m long to pry up a boulder. A small rock is used for a fulcrum and is placed 0.5 m from the resistance end of a lever. Calculate the MA of the board.

• 0.13
• 0.14
• 8
• 7

Three of your friends are all sitting on one end of a seesaw. The combined weight is 275 N. The length from the fulcrum to your friends is 2.5 m. The rest of the seesaw (from the fulcrum to you) is 4.5 m. What effort force is needed to lift your friends?

• 0.006
• 500
• 152.8
• 0.002

Tags

NGSS.MS-PS2-2

NGSS.MS-PS2-4

To lift a refrigerator, you can apply a force of 50 N to the 3 ft end of a lever. The lever applies a force of 550 N to the fridge. How long must the resistance arm be to accomplish this task?

• 0.3 ft
• 3.7 ft
• 0.5 ft
• 4.5 ft

Susan's truck gets stuck in the mud. She uses a tree branch as a lever to lift the truck out. She applies an effort force of 700 N to the branch and the back of the truck weighs 2100 N. What is the mechanical advantage of the tree branch?

• 0.5
• 3
• 0.3
• 4

Tags

NGSS.MS-PS2-1

NGSS.MS-PS2-2

Suppose you exert a force of 2800 N to lift a desk up onto a porch. But if you use a ramp, you need to exert a force of only 1400 N to push it onto the porch. What is the mechanical advantage of the ramp?

• 0.3
• 3
• 0.5
• 2

It takes 130 N to push a 52 kg object up an inclined plane. Calculate the mechanical advantage of the inclined plane.

• 2.5
• 0.4
• 3.92
• 0.26

It has been proposed that the stones of the Pyramids in Egypt were raised by using ramps. Suppose one of these ramps had a mechanical advantage of 3.86. If an input force of 6350 N was provided by the laborers, what would the output force on the stone have been?

• 1,645 N
• 24,511 N
• 5,482 N
• 19,813 N

Tags

NGSS.HS-PS2-1