Work and Machines

Front

What is a machine?

Back

A machine is a device that changes the force or increases the motion from work.

Front

What is mechanical advantage?

Back

Mechanical advantage is the ratio of the output force exerted by a machine to the input force applied to it.

Front

How do you calculate mechanical advantage?

Back

Mechanical Advantage = Output Force / Input Force.

Front

What is the formula for efficiency?

Back

Efficiency = (Output Work / Input Work) x 100%.

Front

What is the efficiency of a machine that does 800 J of work if the input work is 2,000 J?

Back

40%.

Front

How can machines be made more efficient?

Back

Machines can be made more efficient by reducing friction.

Front

What two conditions must be met for work to be done?

Back

An object must move and must move in the direction of the force applied.

Front

What is work in physics?

Back

Work is done when a force causes an object to move in the direction of the force.

Front

What is the unit of work?

Back

The unit of work is the Joule (J).

Front

What is the relationship between work, force, and distance?

Back

Work = Force x Distance.