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thoradicus
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Homework Statement
A horizontal force of 2000N is applied to a vehicle of mass 400kg which is initially at rest on a horizontal surface. If the total force opposing motion is constant at 800N, calculate
(i)the acceleration of vehicle
(ii)the kinetic energy 5s after force is applied
(iii)the total power developed after 5s the force is applied
Homework Equations
F=ma
P=W/t
1/2(m)(v)^2
P=Fv
v=u+at
The Attempt at a Solution
(i)2000-800=400a
a=3ms^-2
(ii)v=(3)(5)
=15m/s
K.E=0.5(400)(15)^2
=45000W
(iii) This part I am not sure of...i tried adding 2 powers together:
P=Fv
=(1200)(15)=18000
18000+(45000/5)=27000 but its not the right awnser