Fnet=P-Pc=24-117.6=-93.6NFind Force Needed to Move 4kg Box in 3s

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Homework Statement


A certain force moves a 4kg box from rest to a velocity of 6m/s in 3 seconds. If the coefficient of friction between the box and floor is 0.05, what is the magnitude of the force?

m=4kg
v0=0
v=6m/s
t=3s
μk=0.05

Homework Equations


a=v/t
F0=mg
P=Ft
P=mv

The Attempt at a Solution


a=(6)/(3)=2m/s
F0=(4)(9.8)=39.2N
Pc=(39.2)(3)=117.6
P=(4)(6)=24
 
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bearsa113609 said:

Homework Statement


A certain force moves a 4kg box from rest to a velocity of 6m/s in 3 seconds. If the coefficient of friction between the box and floor is 0.05, what is the magnitude of the force?

m=4kg
v0=0
v=6m/s
t=3s
μk=0.05

Homework Equations


a=v/t
F0=mg
P=Ft
P=mv

The Attempt at a Solution


a=(6)/(3)=2m/s
F0=(4)(9.8)=39.2N
Pc=(39.2)(3)=117.6
P=(4)(6)=24

HINT:
You've found the acceleration. Can you use that to find the net force, and then, from there, the unknown applied force?You don't need momentum or impulse for this problem.