Energy problem

Actually see when the carpet was lift up at that point of height from ground (where the K.E and P.E are both zero),the K.E goes on decreasing and the P.E goes on increasing......
After reaching that height P.E is max. and K.E is zero.......

Now while coming down the P.E goes on decreasing and K.E is increasing...........................................

Again at last the carpet comes to rest and there the K.E and P.E becomes zero.................................

I hope u can understand.................

Carpet is opening on the inclined plane. Finally the center of mass of carpet is not at ground level it is somewhere at the mid of the inclined plane.

Moreover I didnt get the part where you said at the highest point total energy is not zero (as PE is max and KE =0 ) but on the ground total energy comes out to be zero, so where does the energy go?. why does the loss in PE not comes out to be equal to gain in KE.

I hope u can understand..............

I don't that when the carpet opens up completely, at that moment the COM of the carpet is at rest too.

It must have got some instantaneous velocity, which will certainly be overpowered since the carpet is not free to slide and hence lost to work.

even if all surfaces r frictionless....kinetic energy increases due to obv reason (acc due to gravity)....now the mass of the rolling object (the carpet) is not constant coz as the carpet rolls, it leaves behind some part of it....

the part wich is left behind comes to rest....hence...the energy in the carpet is distributed into the rolling part n the rest part...gradually the carpet opens up fully n all the energy is converted to potential

i guess that shud be the the reason...is it??

n isnt it that the conservation of energy law applies only wen mass is constant??...for physical objects??.. (unless they r travelling at the speed of light of course)

I think if the surfaces are smooth then the carpet will not open...... :)