Eli5 Why is force equal to mass multiplied by acceleration and not speed ?

Question

If a car moves consistently at 80 kmh and it weighs at 600kg, is it not generating any force? since you know, a=0, am I stupid or is Newton ?

In: 13

Answer 1

Force is a change. If you are sitting on the hood of the car going 80 kmh you won’t feel anything.

If you are at rest and it hits you, your speed changes quickly and that’s where the force comes from