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**1. Homework Statement**

A 60.78kg student climbs 4.08m of stairs in 3.85s. Calculate the work required to climb the stairs.

m= 60.78kg, Δd

_{y}=4.08m, Δt=3.85s

**2. Homework Equations**

W=FΔd OR E

_{K}=1/2mv

^{2}

**3. The Attempt at a Solution**

My friends and I are conflicted in how to solve this problem. I believe that because it is the work

*required,*that I must use the first equation, and find the force of gravity (the student only needs to overcome gravity to climb the stairs):

W=FΔd

W=(m)(g)(Δd)

W=(60.78)(9.8)(4.08)

W=2430.228J

W=2.43x10

^{3}J

My friends, on the other hand, believe that we should use the velocity to find the kinetic energy to climb the staircase:

E

_{K}=1/2mv

E

_{K}=1/2(60.78)(Δd

_{y}/Δt)

E

_{K}=1/2(60.78)(4.08/3.85)

E

_{K}=1/2(60.78)(1.06)

E

_{K}=32.2134J

E

_{K}=32.2J

Which one of us are correct? If neither of us are, could you please provide the solution to this problem, or an explanation on how to get there? Thanks in advance!

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