Recent content by clicwar

Thank you very much for the help DocAl. The sentence quoted above is exactly what i was looking for.

The mechanical energy of the system as whole is doesn't changing ... right? (Does the support O of the lever is doing work?) .

I believe that only the gravitational forces are acting on the system "lever+masses". I can't see any other possible force able to do work.

Homework Statement A lever of length 3L can rotate freely around a horizontal axis O. The end of each arm "2L" and "L" of the lever has one mass : "4m" and "9m" , respectively. Find the velocity of mass "9m" at the bottom. Consider that the lever was initially at rest in the horizontal...

Homework Statement A block of mass m rests on a wedge of mass M and height H which, in turn, rests on a horizontal table. All the surfaces are frictionless. If the system starts at rest with the block on the top of the wedge, find the displacement of the wedge during the time the block...

In problems which have a pulley with a certain mass and radius, and a massless string over it, we often consider the tension of the left part of the string different than the tension of the right part of the string. I thought that since the string is massless, the tensions should be the...