this doesnt even make sense
if force = mass x acceleration
then thats like saying a car that weighs 2000 kg traveling at 80 mph and not accelerating will hit you and there will be no force but i would definitely get run over???? (no)
how does this even make sense?
is it only one way, like hitting a car with 50000 m/s^2 of force would make it go 25 mph or whatever? (yes)
note, i understand that pounds is a conversion from newtons (which represents gravitational force = weight), so the numbers aren't exact, but this is more conceptual
thanks, i just need a yes or no, because i can't seem to find one online :)
The acceleration in $F=ma$ is the acceleration caused by the force -- not the acceleration of the object causing the force -- and especially not before it even exerts the force. So if a car hits you, you'd be accelerated backward from whatever your initial speed is to the same speed that the car is going -- that's the acceleration that $a$ represents.
It might be better to remember the formula in the form that Newton originally expressed it, though (updated with modern notation, of course): $$F = \frac{dp}{dt}$$ This tells us that the force is equal in magnitude to the rate of change of momentum of the object the force is exerted upon. Let's say that you have a mass of 70 kg and you're standing still when the car hits you. Then your initial momentum is $0$ kg m/s. The car hits you and in the course of say 0.2 seconds your speed increases to 20 m/s. So your final momentum is $70\cdot 20 = 1400$ kg m/s. Then the force exerted on you is far from 0 N. It is (approximately) $$F\approx \frac{1400-0}{0.2} = 7000\ \text{N}$$