MA for levers

Calculation for Mech Adv for levers

Calculation = distance from fulcrum to effort / distance from fulcrum to resistance.

Ex. MA = 60/6 = 10

** this means that you could lift a resistance of 10 times as heavy as the effort. You could lift a 100-pound rock using only 10 pounds of force.

MA for Wheel & Axle

Mech Adv calculation for Wheel & Axle

MA = diameter of wheel/diameter of axle

Wheel diameter = 20 inches
Axle diameter = 2 inches

MA = 20/2 = 10

What does this mean? It depends...

If you are turning the wheel, the FORCE you apply will be magnified by 10. Thus, the axle will turn with 10 times the force applied to the wheel.

If you are turning the axle, the SPEED will be magnified by 10. Thus, the wheel will turn 10 times faster than that of the axle.

MA for an Inclined Plane

MA Calculation = length of slope/height

If you push a load up an inclined plane, you will move it the length of the slope, which is always longer than the height. Thus, you push the load farther, but you do NOT need to push it as hard.

** Force is applied parallel to the slope **

MA for Wedge

MA Calculation - length of slope/height

** Do not confuse the wedge with the inclined plane -- they are considered 2 different types of machines **

** Force is applied to the short edge **

MA of the Screw

A screw is a simple machine that is actually an inclined plane wrapped around the axle of a wheel and axle. (The inclined planes are the threads on the screw.)

MA = circumference/pitch

Pitch - the vertical distance between the threads of a screw

Circumference - distance around a circle

Circumference = diameter * pi

pi = 3.1416