How Much Power Is Required to Accelerate a Box with Friction Involved?

AI Thread Summary
To calculate the power required to accelerate a 5.0 kg box from 2.0 m/s to 8.0 m/s in 1.8 seconds with a coefficient of friction of 0.220, the net force must be determined by subtracting the frictional force from the applied force. The frictional force can be calculated using the coefficient of friction and the normal force. The work done (W) is then calculated using the net force (Fnet) and the distance moved during acceleration. The power (P) is found by dividing the work by the time taken. Understanding how to incorporate the coefficient of friction into the calculations is crucial for determining the correct net force and ultimately the power required.
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Homework Statement



A 5.0 kg box is sliding across the floor at 2.0 m/s when it is accelerated to 8.00 m/s in 1.8 s. If the coefficient of friction is .220 how much power is required to accelerate the box?

m = 5.0 kg vi= 2.0 m/s vf = 8.00 m/s change in time = 1.8 s coefficient = .22

Homework Equations



Power = Work (W) / change in time (t)
W= Fnetd

Fnet = ma

The Attempt at a Solution


P= w/ t

w= FNetd

Heres my issue. I know Fnet(net force) = ma, which i can easily calculate. The problem is where do i use the coefficient of friction they gave me. Do I need to use it, if i already have Fnet?
 
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You find the force acting against the box and take that away from the force required to accelerate the box to get the net force.
 
Last edited:
So what do i use for the w= Fnetd calculation?
 
F(net)=F(applied)-F(friction)
D= distance the box moved after acceleration
 
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