The Sarcastic Fringehead
Name the six simple machines
lever, wheel and axle, inclined plane, wedge, screw, pulley
A carpenter applies 475 N to the end of a crowbar. The force exerted on the board is 950N. What is the mechanical advantage of the crowbar? MA= output force / input force
2
Find the force needed to lift a 2000N rock, using a jack with a mechanical advantage of 10. MA= Fout/Fin
200N
Where is the output force on a second class lever?
In between the input force and the fulcrum.
What is force measured in?
Newtons
The thread around a screw is a lever
False- inclined plane
The force exerted by your foot on a pedal to ride your bike is an example of ______. :
input force
An inclined plane with one or two sloping sides forms a machine called a ______.
wedge
A winding mountain road is an example of _______.
Inclined Plane
What is the rate at which work is done?
power
What is work measured in?
Joules
Can a machine have a mechanical advantage less than 1?
Yes, output force is less than the input force. Rake
You exert an input force on a hammer. The hammer exerts a(n) _____ force on the nail.
output
Distance is measured in _____?
meters
Power is work divided by ______.
time
Joel does 12 J of work in 2 seconds as he lifts a box off of the floor. How much power does Joel use on the box? P= w/t
6 Watts
What amount of work is being done when you push against an immovable brick wall?
None, it didn’t move.
What efficiency is IMPOSSIBLE to achieve?
100%
A machine that only changes the direction of the force has a mechanical advantage of _____?
1 Example: Fixed pulley
The unit of measure for power is ______.
watt
You can get more work out of a machine than you put into it?
False
An inclined plane wrapped around a cylinder post is a____?
screw
What kind of lever is a soda pop tab?
First class lever
The amount by which a machine multiplies an input force is called the ______.
mechanical advantage
How do you increase an inclined planes mechanical advantage?
Increase the length and decrease the height