Recent content by Sabreen Khan

Thanks a lot Doc Al! it really helped me...i have a few more confusion and problems..please stay around to help me out.

thanks for the reply

[b]1. The so-called Yukawa potential (attached) gives a fairly accurate description of the interaction between nucleons[that is, neutrons and protons, the constituents of the nucleus]. The constants r0 = 1.5x10-15metres and U0 = 50 MeV.[a] Find the corresponding expression for the...

how do i knw when evergy is conserved. A force is conservative if the total work it does on a particle is 0 when the particle moves around any closed path returning to its initial position. examples are gravity and electromagnetic. But how am i supposed to know when this work done is 0? like in...

intial total mechanical energy should equal to final total mechanical energy...is that y the fine is 0?

btw...i understood all da other things very well...thanx..

I still don't get why mechanical energy should be zero? i get that initially it was zero...bt after the block moves down, why shall it be zero ?

what i don't understand about the 1st problem is what my teacher did with the potential and kinetic energy...I completely don't get it...can u help me with that please ?

hey...cant we derive it like this : work done = 0.5mv^2 work done by a stretched spring :0.5kx^2 so..if they are equal... mv^2 = kx^2 right ?

hey phys guru..thanx..its worked..x= 2mg/k ...bt is it like a formula that For maximum extension>>>> mv^2=kx^2 isnt there a way to derive that formula?

no i dint know that...thanx...but what happens after that? which method shall i follow ?

Kinetic and potential energy hello everyone.. please help me solve this problem if you can Q. Two blocks are attached to a light string that passes over a mass-less, frictionless pulley. The two blocks have masses m1= 3 kg and m2 = 5 kg and are initially at rest. Find the...

[b]1. A spring with a force constant k hangs vertically. A block of mass m is attached to the un-stretched spring and allowed to fall from rest. Find an expression for the maximum distance the block falls before it begins moving upward. [b]2. Now..from what i knw F=-kx (k=spring...