Tarzan's Mechanical Energy...?
966840
a)\n\nby dropping 3.2 meters tarzan lost \n\nPE=mgh=688x3.2= 2201.6 J  ,\n\nthis is converted to KE\n\n1/2 * m * V^2 , m=688/9.81= 70.13251784\n\nv=7.92 m/s, \n\nnow we can find centri acceleration\n\na=v^2/r = (7.923635529^2)/18 = 3.488 m/s2\n\nF=70.13 * 3.488 = 244.6 N\n\nso total force is 244.61344+688 = 932.61344 N  \n\nthis is less than 950 N\n\nthe vine doesn't break\n\nb) already found it in part a, max force was \n\n932.61344 N
841940
Tarzan! LOL\n\nIt was call "first born"
613443
Niuchemist is mostly right and deserves the vote, but there is one correction I would make-heavier molecules don't necessarily have less "kinetic energy", they move more slowly-it is the speed of movement that is the critical thing, not the kinetic energy, which is a product of speed *and* mass.
206926
There is no buildup of kinetic energy.  You simply swing your arms to counteract the torque caused by throwing your leg forward.
87652
The most common devices used to convert heat energy to mechanical energy are engines, including steam engines, gasoline engines, etc. If you would like to learn more, I would suggest doing some research on the topic of thermodynamics, which includes the study of heat energy and its conversion to mechanical energy.
31946
reverie's wrong.  Most mass actually comes from kinetic energy, not rest mass.  you can correcly give energy (including heat energy) the same units as mass so it makes sense to say "one pound of heat"... but force is something different entirely.
37744
you can't convert heat energy directly into free energy (electric current).  That would violate the second law of thermodynamics.  you can use a temperature DIFFERENCE to harvest free energy from thermal energy...
44584
Electrical potential energy would be the equivalent of mechanical potential energy, which means the potential to do work.  For example if you lift a 100 Lb weight 10 feet you have done 1,000 foot-lbs of work and the weight now has 1,000 foot-lbs of potential energy that you added.  In a frictionless world, you should be able to get 1,000 foot-lbs of work back out of the weight (for example using pullies and ropes you may use the potential energy in your weight to lift a 10 lb weight 100 feet).\n\nElectrical potential energy would also represent the work that you can get out of an electrical device such as a battery.  Auto batteries are rated in amp-hours.  A battery with say a 50 amp-hour rating should be able to run a starter motor twice as long as a battery rated 25 amp-hours.\n\nElectrical potential energy should not be confused with electrical potential.  Electrical potential is the same thing as voltage.  Therefore a 12 Volt battery may be rated at any number of amp-hours, where heavy duty has the highest rating.
1010100
ok, so if we're assuming that it was a head on elastic collision, and all the energy was transferred then there are two possible situations: if the 25lb ball was sliding then the total energy transferred will be equal to the amount it had originally (since we assumed elastic collision) that is equal to 1/2mv^2...where mass would usually be measured using the metric system. \nif the ball was rolling then it has not only translational energy (1/2mv^2) but also rotational energy which is equal to 1/2Iw^2 where I = inertia of a ball...if it is a solid sphere the moment of inertia is equal to 2/5mr^2 (m = mass, r = radius) and w (omega) = rotational speed in radians per second...which is equal to velocity/radius. so the amount of energy transferred would be equal to 1/2Iw^2 + 1/2mv^2.
767789
decrease potential energy.....through physical factors like friction....
768384
because a car turns heat energy into mechanical energy
193418
Heisenberg notwithstanding, I have never observed my chair turn into energy, even as a transient state, no, not even for an instant.  It must be when I'm not looking.\n\nEnergy, if unused as work, turns into mass... in my case, a mass of fat around the middle.
413533
Props to mathematician.  To expand, a "machine" must transform energy in some way.  The second law of thermodynamics describes that any time energy is transformed, entropy is created.  Whenever entropy is created, the "machine" must expel some energy in order to expel the entropy that has been created (if it doesn't expel the entropy, the machine doesn't run).  So every time a machine does something, it MUST lose some energy, and it cannot run forever.
510921
No it does not. Takes more energy to twist them. If it was the same you would have a perpetual motion machine. No such thing. You are not creating energy you are only transforming it.
1144751
are you hands that big?   better use sunscreen too...\n\nseems if you want attention or maybe you dont want attention either way...would be better to wear a cloth similar to what Tarzan wore...and just rip it off..dont you think.....lol
627909
Kari Byron mentioned they tried the free-energy myth in one show, but i don't remember seeing that one. i need to be on that show when they revisit that myth, it will be great fun for me to confirm it for them!
1131325
Maybe this can help...all you have to do is a search in Yahoo or Google...\n\nhttp://www.think-energy.com/ThinkEnergy/11-14/activities/EnergyTrans.aspx\n\nTry searching for "energy" or "kinetic energy"