Force Calculator (F = ma)
Enter any two of force, mass or acceleration and this calculator solves the third using Newton's second law, F = m x a, in SI units.
How to use the force calculator
- Choose which two values you know, for example mass and acceleration.
- Type the two known values and leave the third blank.
- Read off the solved force, mass or acceleration.
Examples
Mass and acceleration
m = 10 kg, a = 9.8 m/s^2
F = 98 N
Force and mass
F = 98 N, m = 10 kg
a = 9.8 m/s^2
Frequently asked questions
What is Newton's second law?
Newton's second law states that the net force on an object equals its mass times its acceleration, written F = m x a.
What units does this calculator use?
Force is in newtons (N), mass is in kilograms (kg) and acceleration is in metres per second squared (m/s^2). One newton is one kg x m/s^2.
How many values do I need to enter?
Exactly two of force, mass and acceleration. From any two the remaining quantity is fully determined.
How do I find weight as a force?
Weight is a force, so set acceleration to 9.8 m/s^2 (gravity on Earth) and enter the mass to get the weight in newtons.
Why can't mass be zero when solving for acceleration?
Acceleration equals force divided by mass, and dividing by zero mass is undefined, so that combination is rejected.
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