StudyFrame

Force calculator

Fill in what you know and leave the unknown box empty — it works out whichever one is missing. Nothing is uploaded; the arithmetic happens in your browser.

Force = 686.7 N

The formula

F = ma

Where this usually goes wrong

Mass in kilograms, not grams. Weight is a force: use a = 9.81 m/s².

Worked example

A 70 kg person weighs 687 N.

Those numbers are already in the boxes above — press Work it out to see it, then change them for your own.

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