​Force must act in the same direction as the 

object moves

Force:

The product of force and distance

(W=FxD

Definition: ​

Work​

​When there is NO movement: the direction of the force and the direction of the movement are different.

When Work is NOT Done​:

Object moves in the direction of the force.​

​When is Work Done:

Work Equation: ​

​Work: Joules

Force: Newtons

Distance: Meters ​

Power

The rate of doing work​

(Power=Work/Time)​

Work-Joules

Power- Watt

Time- Seconds​

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​Machine

Something that changes a force; makes work easier to do​

​Simple Machines

​There are 6 simple Machines:

• Lever

• Wheel and axle

• Pulley

• Inclined plane

• Wedge

• Screw

​A simple machine is a mechanical device that changes the direction or magnitude of a force. In general, they can be defined as the simplest mechanisms that use mechanical advantage (also called leverage) to multiply force.

​Compound Machine

Two or more simple machines that operate together

​Input

The amount of force, distance, or work made by the person while using a machine

​Output

The amount of force, distance, or work made by a machine doing something

Efficiency

The percentage of work input that becomes work output, less than 100% due to friction

The mechanical advantage of a machine in the absence of friction

​Ideal Mechanical Advantage

The mechanical advantage of a machine by measuring the ratio of output force to input force

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​Actual Mechanical Advantage

Mechanical Advantage