What is a grooved wheel with a rope wrapped around it?
A pulley.
100
What attaches muscles to bones?
Tendons.
200
What is work?
When a force is exerted on an object, causing that object to move some distance.
200
What is output force?
The force exerted by the machine.
200
What are the six simple machines?
The inclined plane, the wedge, the screw, the lever, the wheel and axle, and the pulley.
200
What is the fixed point that a lever rotates around?
A fulcrum.
200
What is the formula for the mechanical advantage of a machine?
What is a machine's mechanical advantage?
Mechanical advantage = output force/input force
A machine's mechanical advantage is the number of times a force exerted on a machine is multiplied by the machine, or the number of times a machine increases a force exerted on it.
300
What is power?
The rate at which work is done.
300
What is a machine? Do machines change the amount of work being done.
A device with which you can do work in a way that is easier or more effective. Machines do not decrease or increase the amount of work being done. They just make it easier to do work.
300
An ax, a zipper, and teeth are all examples of what type of simple machine?
A wedge.
300
A car's steering wheel and a screwdriver are examples of what type of simple machine?
A wheel and axle
300
What is the difference between real machines and ideal machines?
Ideal machines have the efficiency of 100%. Real machines can not reach the efficiency of 100% because friction interferes with it. Friction decreases the efficiency of a machine.
400
What is the formula used to calculate work?
Work = Force x Distance
400
What are the three ways that machines can make work easier?
Change force, change direction, or change distance.
400
What is a compound machine?
A machine that is made up of two or more simple machines.
400
Where is the fulcrum located when you bend your arm at the elbow?
The elbow
400
The more efficient a machine is, the closer the actual mechanical advantage is to the ______________.
Ideal mechanical advantage.
500
What is the formula used to calculate power?
Power = (Force x Distance)/Time or Work/Time
500
You do 1,500 J of work using a screwdriver. The screwdriver does 500J of work on a screw. What is the efficiency of the screwdriver?
Efficiency = output work/input work x 100%
Efficiency = 33.3%
500
What type of pulley changes the direction of the force, but does NOT change the amount of force applied?
A fixed pulley
500
When you divide the radius of the wheel by the radius of the axle, what are you calculating?
The ideal mechanical advantage of a wheel and axle.
500
What are the six simple machines? Define each one.
Inclined plane - A flat slanted surface.
Wedge - A device that is thick on one end and tapers to a thin edge at the other.
Screw - An inclined plane wrapped around a cylinder.
Pulley - A grooved wheel with a rope wrapped around it.
Wheel and axle - Simple machine made of two circular objects fastened together that rotate together around a common axis.
Lever - A rigid bar that is free to pivot, or rotate, about a fixed point.