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If mechanical energy is conserved, then a pendulum that has a potential energy of 20 J at its highest point and 0.5 J at its lowest point has _____ as its kinetic energy at its lowest point.

20 J
0.5 J
19.5 J
20.5 J

2 Answers

1 vote

Answer:

The third answer is correct:)

Step-by-step explanation:

User Chris HG
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At the highest point: kinetic energy is 0 due to the speed is 0

So the total mechanical energy is 20

Assume no frictions present, then the mechanical energy is conserved

So at the lowest point, kinetic energy = mechanical energy - potential energy

Answer will be 20 - 0.5 = 19.5 J
User Centralcmd
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