Question

What force is required to give a 1kg body a velocity of 5m/s after acting for 5sec?

I know I can use F=mxa


What do I do with the 5sec?
Thanks

Answer 1

Yea, you get to use F=MxA
where, M=mass, A=acceleration.
if you expand the equation, you notice
F=MxA
where A=velocity change / time taken for change
therefore, f = 1kg x (5ms/5secs)

Answer 2

The basic form of Newton's second law is
Force = rate of change of momentum

= change of (m V) /time

if m is constant this is the familiar form
F = m dV/dt = m A
but here it is simple to use the more fundamental form
change of momentum/time
= m v/t = 1 *5/5 Newtons
as Francis said.