Force Calculator (F = ma)
Newton's second law: solve force from mass and acceleration, with weight and g-force conversions.
Force (N)
686.70
Breakdown
- Force (kN)
- 0.69
- Force (lbf)
- 154.38
- Acceleration in g
- 1
- Weight on Earth (N)
- 686.70
- Second mass force (N)
- 981
Last updated:
FAQ
What is the difference between mass and weight?
Mass is the amount of matter in kilograms and stays constant everywhere. Weight is the force gravity exerts on that mass — your 70 kg body weighs about 687 N on Earth but only 113 N on the Moon.
How much force is 1 g?
One g is 9.81 m/s² — the acceleration of free fall at Earth's surface. A force of 1 g on a 70 kg adult is therefore about 687 N, what your chair pushes back with right now.
Why multiply by 4.448?
One pound-force is defined as exactly 4.4482216 newtons, the weight of one pound mass under standard gravity. The conversion is exact by international agreement since 1959.
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