11:17 AM
1

In part (b) of this question, they have stated that the current that flows through the aeroplane is 0.00 A. When you use the value for emf from part (a) and the resistance, you can calculate that I = V/R = 0.490/1.78 = 0.275 A. I don't understand how they concluded that there must be no current i...

9 hours later…
8:06 PM
2

I am aware of this SE question, however, it does not solve my problem. Assume that a bulk uniformly charged nonconductive sphere is set in motion along the \$x\$-axis in the lab frame of reference. Since the electrical field complies with the inverse square law everywhere outside the sphere, some m...

3 hours later…
10:37 PM
1

I came across an interesting discussion at the start of chapter 3 of MWT Gravitation. It reads: Here and elsewhere in science, as stressed not least by Henri Poincare, that view is out of date which used to say, "Define your terms before you proceed." All the laws and theories of physics includi...

1

The first law states that \$ \Delta U = Q - W \$ where W is the work the system does on the outside. If there is no heat added, the change in energy is equal to the work done. If the work is negative, i.e. the outside is doing work on us, we get \$ \Delta U = W \$. But in mechanics, \$W = \Delta \$ K...