Simple gravity powered generator, built out of lego parts. It uses a gear ratio of 1:42. I'm fairly pleased with the efficiency rating of 28%, considering the short time it took to build. I hope to make an improved version in the future.
Stats (with only one resistor):
Weight = .45 kg
Height = .69 m
Voltage = 2.3 V
Resistance = 1kOhm
Time = 160 s
Input Energy = m*g*h = 3 J
Output Power = V^2/R = 5.3 mW
Output Energy = P*s = .85 J
Efficiency = Jout/Jin = 28%
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