## Finding magnitude of force (involving mass at velocity from rest in seconds with coef

1. The problem statement, all variables and given/known data
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
2. Relevant equations
a=v/t
F0=mg
P=Ft
P=mv

3. 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
1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution
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 Quote by bearsa113609 1. The problem statement, all variables and given/known data 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 2. Relevant equations a=v/t F0=mg P=Ft P=mv 3. 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.
 thank you so much

 Tags coefficient, force, friction, magnitude, physics