# Convert velocity to newtons?

by NutriGrainKiller
Tags: convert, newtons, velocity
 P: 61 Working out some simple physics and I can't figure out how to convert velocity to newtons for force.. A six pound (2.72kg) tonka truck is moving across a cardboard bridge at a constant velocity of .067m/s (estimated). I tried looking for a while but was unable to find the kinetic friction of plastic wheels on cardboard. Using newton's second law, I was able to make this equation: F-Fk=ma, so F = ma+Fk. Fk is muK*Fn, so the final equation is: F=ma+muK*fn. Because there is no movement in the Y direction, fn would be the weight, and in this case 26.7n. there is no acceleration, so would ma equal zero? Is there any way to find the kinetic friction between plastic and cardboard? Thanks guys!
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 Quote by NutriGrainKiller Working out some simple physics and I can't figure out how to convert velocity to newtons for force..
Not surprising, since you can't "convert" velocities into forces in the first place.
What do you mean by this?
P: 61
 Quote by arildno Not surprising, since you can't "convert" velocities into forces in the first place. What do you mean by this?
Well I think I answered that in my initial post, however there are more questions further down

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## Convert velocity to newtons?

What exactly are you trying to figure out? Is the truck moving at constant velocity? Are the wheels rolling?
 PF Patron P: 7,122 It is really something you'd have to look up and you'd have to know the exact dimensions of what the tire is that is actually touching the ground. Also, as arildno pointed out, velocity and force are two different things. It is like comparing temperature to density.
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 Quote by NutriGrainKiller Well I think I answered that in my initial post, however there are more questions further down
You can't convert a velocity into a force! Period.
P: 61
 Quote by Doc Al What exactly are you trying to figure out? Is the truck moving at constant velocity? Are the wheels rolling?