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Units of force
Beginner
One newton accelerates one kilogram at one metre per second squared.
1 N = 1 kg·m/s²One newton gives 1 kg an acceleration of 1 m/s². Weight of an apple (~0.1 kg) is about 1 N. A kilogram-force is 9.8 N, an older unit.
A 70 kg person weighs about 686 N.
Mass in grams must be converted to kg before using F = ma.
In more detail
The newton is the SI unit of force: one newton accelerates one kilogram at one metre per second squared. It is a derived unit built from base units.
Real-world uses
- Lift and crane specifications are quoted in newtons or kilonewtons.
- Weight of an object is expressed in newtons using W = mg.
- A 1 kg apple weighs about 9.8 N on Earth, which helps explain why newtons are the natural unit for weights and push forces.
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Frequently asked questions
How many newtons is one kilogram of weight on Earth?
About 9.8 N, since weight equals mass times g.
Is a newton a unit of mass?
No. Mass is measured in kilograms, and force in newtons.
How heavy is one newton?
About the weight of a small apple, roughly 0.1 kg of mass on Earth.
Related topics in Newton's Laws & Forces
Newton's first law · Inertia · Newton's second law · Newton's third law · Weight and normal force · Free-body diagrams