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Warmacblu
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Homework Statement
A simple Atwood's machine uses two masses m1 and m2. Starting from rest, the speed of the two masses is 8.7 m/s at the end of 7.4 s. At that time, the kinetic energy of the system is 61 J and each mass has moved a distance of 32.19 m.
Find the value of the heavier mass.
Find the value of the lighter mass.
Homework Equations
a = (m2 - m1) / (m1 + m2)g
Ke = 1/2mv2
The Attempt at a Solution
61 = 1/2m1v2 + 1/2m2v2
61 = 1/2(8.7)2(m1+m2)
61 = 37.845(m1+m2)
m1+m2 = 1.612
a = 8.7 / 7.4 = 1.176
1.176 = (m2 - m1) / (m1 + m2)g
10.976m1 = 8.624m2
m1 = .786m2
.786m2 + m2 = 1.612
2m2 = 2.051
m2 = 1.025
m1 + 1.025 = 1.612
m1 = .587
I was sure that I solved it correctly, perhaps my algebra for solving the acceleration equation is incorrect.
Thanks for any help.