Physics: Work, Energy, and Simple Machines

Flashcards for key concepts in physics related to work, energy, and simple machines, based on lecture notes.

What is the unit of work?

Joules (J)

What formula is used to calculate work?

Work = Force × Distance

What is the force needed to move a 50 kg mass straight up?

490 N (using F = ma with g = 9.8 m/s²)

What does MA stand for in the context of machines?

Mechanical Advantage

What is the formula for Mechanical Advantage (MA)?

MA = FR / FE, where FR is resistance force and FE is effort force.

What is the relationship between work done with a machine (WE) and work done without a machine (WR)?

WE = WR or WE > WR.

What are the units of acceleration due to gravity?

Meters per second squared (m/s²).

1 kg is equivalent to how many pounds?

2.2 pounds.

What device allows changing the direction and magnitude of a force?

A machine.

What is the purpose of a lever?

To lift or move loads with less effort.

What are the three classes of levers?

First class, second class, and third class.

What does an inclined plane do?

Reduces the amount of force needed to lift an object by spreading the required work over a longer distance.

What happens to the force needed when using a ramp to lift a box?

It reduces the amount of force needed compared to lifting without a ramp.