Is the Energy of Simple Pendulum conserved ?

Answer 1

Technically speaking, yes: energy is conserved. The kinetic energy will gradually be converted into thermal energy but it is still conserved. Conservation of energy simply means no energy is created or destroyed i.e. the sum of the energy at the beginning is the same as the sum of the energy at the end.

The only time energy isn't conserved is in quantum mechanics (quantum field theory) and then the Uncertainty Principal applies.

Answer 2

It basis <16 old years physic lessons - Absolutely!
In real life - No chance. You have air resistance for a start and losses through friction in pivot joint into heat... and other stuff too. The more equations learn't the better the picture.
Basically, Energy is conserved if there are no losses. Energy has the right to be free man! ....and it usually will be at every opportunity. Use your imagination to consider possible ways for energy to liberate and you'll be on the right path. Except Gravity which nobody understands - from an energy perspective anyways.

Answer 3

Energy in all scenario is conserved. It can neither be created nor destroy.

The reason why the pendulum slows down would be because there is air resistance and resistance at the joint between the bar/string of the pendulum and the fixed point. Kinetic energy, in this case, has been transformed into heat and sound energy.

Answer 4

Let h = L(1 - cos(theta)) be the height of the bob above the bottom of its arc on a pendulum length L with angle theta relative to the vertical. Let m be the mass of the bob on the end of the pendulum and g be the gravity field. Then the potential energy of the pendulum (bob) is PE = mgh = mgL(1 - cos(theta)) and all that energy is conserved (saved) when it becomes all kinetic energy at the bottom of the swing where theta = 0 so that h = 0. So the potential energy becomes kinetic energy KE = 1/2 mv^2; where v is the tangential velocity v = wL of the bob and w is the angular velocity of the swinging pendulum. From the conservation of energy we can write PE = mgL(1 - cos(theta)) = 1/2 mv^2 = KE, meaning, barring friction and such loses, all that potential energy at the top of its arc will equal all that kinetic energy at the bottom of its arc. Your answer, without the tekkie stuff is "all that potential energy at the top of its arc will equal all that kinetic energy at the bottom of its arc" ANS

Answer 5

Yes the energy of a simple pendulum is conserved. in practise it would not be because of fiction or air resistance or what-have-you. But the use of the 'simple' implies that the resistive forces are ignored for this hypothectical pendulum.

Answer 6

If you had it in a vacuum, and had no friction from the motion of the string, yes, it would keep going forever; however, you would never be able to get rid of absolutly all the friction caused by the motion of the string.

Answer 7

NO
No energy can be conserved fully. Friction causes heat and sound so energy will be lost in heat energy and sound energy even if it only a small percentage.

Answer 8

Energy can be niether created nor destroyed, merely transformed.

Answer 9

any time there is motion there is friction and friction eat available energy so there is a loss of energy.