# Force measurement [closed]

We have a bike and a biker on it of mass 81 kg combined. Biker can reach speed around 30k/h.

And the question is: how to measure the force (in Newtons) applied on the bike to reach that speed in 10 seconds.

## closed as off-topic by Thomas Fritsch, John Rennie, tpg2114♦Jun 8 at 22:20

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• The force can be as low or as high as you wish, it depends on the time over which the force is acting. – Jasper Jun 7 at 9:35
• Do you mean a period of time in which the biker reaching that speed? Didn't thought about that. Let's say biker have 10 seconds to reach that goal. – user71305 Jun 7 at 9:45

F = ma ---- (1)

v = u +at ---(2)

let's say bike is starting from rest i.e u =0

v~ 8.61 m/s (converting to m/s)(i am assuming k refers to kilometres)

from equation 2 we get a = 8.61/10

plug in the values in equation 1

we get f =81*8.61/10 = 69.741~70 newton

• Thanks! That helped. Unfortunately can't vote for the answer due to my status. – user71305 Jun 7 at 10:59