Understanding Mass and Weight: What's the Difference?

FreeAstroScience.com wants to be your everyday science guide putting in your mind new notions in a simple way, as we like. Now we are going to discuss in this educative article a basic physical topic, the Difference between Mass and Weight. When you want to measure our bodies, we often use the term "weight" to denote that value. However, many people confuse mass and weight, believing that are the same thing, indicating the "tonnage" of a body. In reality, there are deep differences between the two concepts. Let's find them out together.

Understanding Mass and Weight

Lets start with mass, which refers to the amount of matter in a body. You know that number you see on the scale seemingly increasing after the holiday season? Well that represents your mass. On the hand weight takes into account the force exerted on an object due to gravity. This force depends on where you're located. Whether it's Earth or another celestial body like a planet or satellite. On Earth specifically this force of gravity is 9.8m/sec². Is commonly denoted as "g."

To illustrate this further lets consider an example; if a body weighs 35 kg on Earth it would weigh only about 5.8 kg on the Moon. This difference arises because the Moons gravity is one sixth of Earths pull. As seen in videos, from Apollo missions astronauts appear to float while moving across our satellite.

It's important to understand that the mass of an object remains the same whether you're, on Jupiter, Mars or experiencing weightlessness on the International Space Station.

Regarding measurement units; Mass is typically measured in kilograms while weight is measured in Newtons. A Newton represents the force required to accelerate a kilogram of mass by 1 m/sec². Since the acceleration due to gravity on Earth remains relatively constant regardless of location the unit "kg weight" has become widely used. This unit represents the force needed to accelerate a kilogram of mass, by 9.8m/sec², which aligns with "kg mass." So when we say "I weigh 75 kg " it would be more accurate to refer to it as "kg weight."