Question

in the context of the loop and junctions rules for electrical circuits a junction is:
a) where a wire is connected to a resistor
b) where a wire is connected to a battery
c) where only two wire are joined
d) where three or more wire are joined
e) where a wire is bent

My answer: According to my book a junction is a branch where currents split off and come together. Then it says usually a resistor is connected in each branch. So I chose A.

"The sum of the emfs and potential differences around a closed loop equals zero" is a consequence of:
a) Newton's third law
B) ohm's law
c) Newtons second law
d) conservation of energy
e) conservation of charge

My answer:
For this one I am not to sure what to pick so I choose d. In the book it says the Loop rule: The algebraic sum of the changes in potential encountered in a closed loop of a circuit must be zero or Kirchhof's loop rule.

Thank you

Susane: Your book is right on the branch. It is branches that join at a junction. Currents split at the junction, and go to the branches. Answer a is silly. What is wrong with d?

On the second, d is the best answer.