Calculating weight
On the Earth’s surface the weight of a mass of 1 kg is 10 N.
We say that the strength of gravity is 10 N/kg or on Earth, gravity = 10 N/kg.
Weight is calculated using the equation:
Weight = mass x gravity
W = mg
W = weight in N
m = mass in kg
g = gravity in N/kg
On the Earths’ surface g = 10 N/kg
| W = mg | W = m x g |
| m = \(\frac{\text{W}}{\text{g}}\) | m = W ÷ g |
| g = \(\frac{\text{W}}{\text{m}}\) | g = W ÷ m |
| W = mg |
| W = m x g |
| m = \(\frac{\text{W}}{\text{g}}\) |
| m = W ÷ g |
| g = \(\frac{\text{W}}{\text{m}}\) |
| g = W ÷ m |
Example
Find the weight of a person on Earth if they have a The amount of matter an object contains. Mass is measured in kilograms (kg) or grams (g). of 65 kg (g = 10 N/kg)
Answer
W = mg
m = 65 kg
g = 10 N/kg
W = 65 x 10
W = 650 N
The weight of the person is 650 N.
