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RichardCory
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Homework Statement
Kelli weighs 435 N, and she is sitting on a playground swing seat that hangs 0.44 m above the ground. Tom pulls the swing back and releases it when the seat is 1.00 m above the ground. Assume that air resistance is negligible.
(a) How fast is Kelli moving when the swing passes through its lowest position?
SOLVED: 3.31 m/s
(b) If Kelli moves through the lowest point at 2.0 m/s, how much work was done on the swing by friction?
SOLVED: 154.284 Joules
V at bottom in closed system = 3.31 m/s
V at bottom in open system = 2.0 m/s
Kelli's mass = 44.388 kg
K in closed system = 243.158 Joules
Homework Equations
K = .5mv2 = J(oules)
W = Fd = J(oules)
The Attempt at a Solution
I attempted to use the difference of the two velocities to find the kinetic energy in Joules, and it did NOT work.
Any suggestions?
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