Recent content by giladsof

It's a given that the rectangle is fixed to the ground.. So apart from the fact that the magnetic field in it changes direction all the time, B's size is constant

Where is my mistake? I have a feeling it's in the calculation of B... ?

Thank you I solved it. One small question remains- I don't understand why is it so intuitive that the capacitor will resist this change?

well usually in these kind of questions where there is some kind of change in the capacitor (the plates were move closer for instance)- We need to calculate the energy in the system before the change, calculate the energy afterwards and see the change's size and sign. But in this problem I...

Homework Statement Homework Equations U = 0.5CV^2 The Attempt at a Solution I'm really lost on this one...?

Cheers... very helpful...

this is the wrong answer... the question is where is my mistake...?

very close.. but not quite there

OK... As I try your idea I get into the following dilemma: which way is V? The movement of the rod or the movement of the current? Unfortunately neither one of those options creates a force upwards using the right hand rule... \: