(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

a) How much work must you do to push a 13.0 kg block of steel across a steel table ([tex]\mu_{k}[/tex]=0.6) at a steady speed of 1.30 m/s for 8.30 s?

b) What is your power output while doing so?

2. Relevant equations

[tex]W=\vec{F}*\Delta S[/tex]

[tex]F_{f}=u_{k}*n[/tex]

[tex]F=ma[/tex]

3. The attempt at a solution

First I applied Newton's Second and performed the following:

[tex]F=ma[/tex]

[tex]F-F_{f} = ma[/tex]

To find [tex]F_{f}[/tex], I used [tex]F_{f}=u_{k}*n[/tex] using [tex]mg[/tex] for [tex]n[/tex] and [tex]0.6[/tex] for [tex]u_{k}[/tex].

[tex]F_{f}=u_{k}*mg[/tex]

[tex]F_{f}=(0.6)*(13)(9.8)[/tex]

[tex]F_{f}=76.44 N[/tex]

Throwing that back into the NII equation along with substituting the other variables, I got:

[tex]F-76.44=(13)(9.8)[/tex]

[tex]F=93.94 N[/tex]

I think I may have done something wrong in that step.

Anyways, if that is correct then this is where I am stuck. I do not know how to apply this information to conclude the work done over the time period supplied.

To solve B, I assume I will simply use the equation [tex]P=\frac{\Delta E}{\Delta t}[/tex], where I would use the time supplied for the t value and the answer from part A to the E value.

Any help would be greatly appreciated, thanks!

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# Homework Help: Work with a given time period

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