Simple Machine
A flat surface with one end higher than the other
Inclined plane
Walter and Helen are asked to paint a house. Walter can paint the house by himself in 12 hours and Helen can paint the house by herself in 16 hours. How long would it take to paint the house if they worked together?
6.9 hours
A 50-kg person runs up the stairs 10 meters high in 2 minutes. Acceleration due to gravity (g) is 10 m/s2
5000 J
A man does 100 J of work to move a box up an inclined plane, the amount of work produced is 80 J.
80%
9m input 3m output
3
Wedge
Tom and Jerry have to stuff and mail 1000 envelopes for a new marketing campaign. Jerry can do the job alone in 6 hours. If Tom helps, they can get the job done in 4 hours. How long would it take Tom to do the job by himself?
12 hours
Calculate the power required of a 60-kg person climbs a tree 5 meters high in 10 seconds. Acceleration due to gravity is 10 m/s2.
A man does 100 J of work to move a box up an inclined plane, the amount of work produced is 45 J.
45%
12m input 3m output
4
A straight bar that pivots on or around a fulcrum
Lever
One pipe can fill a swimming pool in 10 hours, while another pipe can empty the pool in 15 hours. How long would it take to fill the pool if both pipes were accidentally left open?
30 hours
A rotary comedy with power of 300 watts and period 5 minutes rotates 5 rounds. The energy it uses is ….
450 kJ
A man does 100 J of work to move a box up an inclined plane, the amount of work produced is 75 J.
75%
25m input 5m output
5
A chain, belt, or rope wrapped around a wheel
Pully
One roofer can put a new roof on a house three times faster than another. Working together they can roof a house in 5 days. How long would it take the faster roofer working alone?
3.3 days
You’re riding a toboggan down an icy run to a frozen lake, and you accelerate the 80.0-kg combination of you and the toboggan from 1.0 m/s to 2.0 m/s in 2.0 s. How much power does that require?
60 W
A man does 100 J of work to move a box up an inclined plane, the amount of work produced is 60 J.
60%
100m input 10m output
10
An inclined plane that is wrapped around a cylinder
Screw
Triplets, Justin, Jason, and Jacob are working on a school project. Justin can complete the project by himself in 6 hours, Jason can complete the project by himself in 9 hours, and Jacob can complete the project by himself in 8 hours. How long would it take the triplets to complete the project if they work together?
2.5 hours
A machine does 40J of work in 5 seconds. How much power is that?
8 W
A man does 100 J of work to move a box up an inclined plane, the amount of work produced is 65 J.
65%
500m input 5m output
100