Answer:
Student b
Explanation:
Because, Battery pumps the charges around the circuit. Here, charges are the free electrons. And this charges are already present in the conductor. When we connect this conductor with the battery - It set up an electric field and The diffrence between the potential between the ends of the wire pushes this free charges to move in perticular direction. (This is called electric energy)
This electric energy is converted by chemical reactions in the battery. When the battery is dead - It means that the chemical energy producing chemicals has been consumed. thereafter there will be no more chemical reactions takes place to produce electric energy. Hence we say that the battery is dead.
Answer:
This is a conceptual problem so I will try my best to explain the impossible scenario. First of all the two dust particles ara virtually exempt from any external forces and at rest with respect to each other. This could theoretically happen even if it's difficult for that to happen. The problem is that each of the particles have an electric charge which are equal in magnitude and sign. Thus each particle should feel the presence of the other via a force. The forces felt by the particles are equal and opposite facing away from each other so both charges have a net acceleration according to Newton's second law because of the presence of a force in each particle:

Having seen Newton's second law it should be clear that the particles are actually moving away from each other and will not remain at rest with respect to each other. This is in contradiction with the last statement in the problem.
Answer:
see below
Explanation:
First: Leave a couple inches of wire loose at one end and wrap most of the rest of the wire around iron u-shaped bar and make sure not to overlap the wires.
Second:Cut the wire (if needed) so that there is about a couple inches loose at the other end too.
Third: Now remove about an inch of the plastic coating from both ends of the wire and connect the one wire to one end of a battery and the other wire to the other end of the battery.
Refraction occurs when a wave enters a new medium and changes its speed.
i hope this helps