Any force that acts upon an object causes the object to move, or more appropriately, *accelerate*. An apple falling from a tree (the force) hits a basket ball (the object) and the basketball begins to move faster and faster (acceleration), until it loses the acceleration and slows down.

Considering the ball has a mass of 1kg (mass is an objects weight on Earth less its gravity). Then the acceleration of the ball is measured by its speed per unit of time.

**Newton Unit**

With this in mind, **1 Newton (N)** is equal to an object with a mass of **one kilogram** (1kg) moving at a speed of **one meter per second each second**.

**1 N = (1m/sec²) or simply put, 1 Newton = Mass x Acceleration**

The Newton represents the force on an object or the **work** done, referred as the energy times the distance the force moves.

Units of newtons have no relative association to the real world, unless we add a distance factor; that is, unless we can describe how far this force has accelerated over a certain distance. Enter the Joule.

**Joule**

1 joule is a unit of energy (or work done) that equates to a mass of 1 kg that is accelerating at 1 meter / second over 1 a distance of 1 meter. A more specific way to describe a joule is N times meters.

**J = N x M, or simply put, 1 Joule = (Mass x Acceleration) x (distance). **

If we lift our 1kg basketball 1 meter, we have 1 joule.

To gain more perspective on Joules, please view this video https://www.youtube.com/watch?v=JqaQ04G7Ork

**Watt**

1 watt is equal to 1 joule / second or 1 kg that has moved a distance of 1 meter at a velocity of 1 meter / second squared for 1 second.

Reverting back to the apple example, if the basketball of mass 1 kg is moving at 1 meter/second over a distance of 1 meter (joule) and it did this in 1 second, we have a watt. Another example would be moving 1 lb about 9 inches.

**erg**

1 erg = 10^{−7} joules or 10 over 7 zeroes.

An example would be the sun’s luminosity (brighness) is equal to 3.846×10^{26} W or 3.9 x 10 ^{33} **ergs**/sec.