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jperez94
Feb10-04, 06:04 PM
Hey guys, just a quick question. If you have a pendulum of length L and a bob of mass M, and if you bring the string to a horizontal position and then give the bob a minimal initial speed enabling the pendulum to make a full turn... the maximum kinetic energy of the pendulum will be when it reaches the bottom... at mg=tension...right?

PiRsq
Feb10-04, 06:41 PM
Yes, since the pendulum had gravitational potential energy relative to its position before, all of the gravitational energy plus that little kinetic energy given will be converted fully to kinetic energy when the gravitational potential is zero which is at the bottome as you say it

Doc Al
Feb10-04, 07:50 PM
Originally posted by jperez94
.... when it reaches the bottom... at mg=tension...right?
Just a comment: at the bottom, the tension in the string will not equal mg; it will be greater than mg.