 # 11.2 notes.  In other words, all the kinetic energy in a system plus all the potential energy of a system is total amount of mechanical energy in the.

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11.2 notes

 In other words, all the kinetic energy in a system plus all the potential energy of a system is total amount of mechanical energy in the system.

 So, if you calculate that 42% of the energy a falling object has is kinetic energy, then ________% must be potential.

All the kinetic energy plus all the potential energy before something happens equals all the kinetic energy plus all the potential energy after the event. This is called Conservation of Energy

K before + Ug before = K after + Ug after

1/2mv 2 + mgh = 1/2mv 2 + mgh

 Tarzan, mass 85 kg, swings down on the end of a 20m vine from a tree limb 4.0 m above the ground.  How fast is Tarzan moving when he reaches the ground?  Does your answer depend on Tarzan’s mass?  Does your answer depend on the length of the vine?

 m = 85 kg  h = 4 m  l = 20 m

Kinetic energy before is… Potential energy after is… Come on, think!

0 + (85)(9.8)(4) = 1/2 (85)v 2 + 0 v 2 = v =

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