Mass Vs Weight
We use the words mass and weight interchangeably in everyday conversation but in science there are two different things.
Mass is the amount of atoms that make something up. It is measured in kg or grams.
Weight is the effect of gravity on your mass. It is measured in Newtons (N). Your weight can change when the force of gravity changes so on the moon your weight will be less.
Calculating weight
Weight can be calculated by multiplying the mass and the gravity together. Gravity on Earth is 9.6 N/Kg but to make calculations simpler we use 10.
So for every 1 kg it is 10N, this means that if someone has a mass of 120 Kg their weight is:
120 kg x 10 N/kg = 1200N
The triangle can be rearranged to calculate mass and gravity..
Use the following equations
Mass = Weight ÷ gravity
Gravity = Weight ÷ mass.
For example if an astronauts weight on Jupiter is 2500 N and their mass is 100 kg we can find the strength of gravity on Jupiter.
Gravity = 2500 ÷ 100
= 25 N/ kg
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