Levers & Pulleys
A simple machine that is a bar that pivots on a fixed point
A simple machine that is two cylindrical or circular objects attached to each other.
What is a Wheel & Axle?
A simple machine that is a flat, sloped surface.
What is an inclined plane?
A device that makes work easier.
What is a machine?
The SI (metric) unit for measuring work.
What is a Joule (J)?
A simple machine that is a rope wrapped around a wheel
What is a pulley?
A simple machine that has a wide opening that tapers into a point. OR – An inclined plane that moves.
What is a wedge?
A simple machine that is an inclined plane wrapped around a cylinder.
What is a screw?
Two or more simple machines working together.
What is a compound machine?
The fixed point on a lever.
What is a fulcrum?
There are THREE types of pulleys – name them.
What are fixed pulley, movable pulley, and pulley system?
Name two examples of a wheel & axle found on a car:
What is the front/back wheel and axle and the steering wheel and axle?
Another name for an inclined plane is a _____.
What is a ramp?
The force you exert on a machine is called a(n) ______ _____.
What is an input force?
The work done by a machine as the output force acts through the output distance.
What is output work?
How many “classes” of levers are there?
What is THREE (3)?
What is the main purpose of a wedge? Why would someone use a wedge?
What is to split things into two or cut something?
The mechanical advantage of an inclined plane = length of ramp ÷ height of ramp. What is the mechanical advantage of a ramp this is 10 feet long and 5 feet high?
The number of times a machine increases a force exerted on it.
What is mechanical advantage (MA)?
The percentage of the input work that is converted to output work.
What is efficiency?
A seesaw in an example of what class of lever?
Input-------▲-------Output
(Fulcrum)
What is first-class lever?
How does a wedge make work easier? Does it change your force, your distance, or your direction?
What is change the force / direction? You push down and it exerts force out in both directions.
Name THREE examples of inclined planes:
What is a ramp, wheelchair ramp, stairs, hill, skateboard ramp, escalator, highway ramp, slide, roof, slope, ski slope, etc. (any THREE of these)
Machines make work easier by doing one of THREE things. What are they? Must name all 3 to get credit!
What is change SIZE of force, change DISTANCE of force, and/or change DIRECTION of force?
The rate at which work is done.
What is power?