A student assumes that current leaves a junction and calculates
PHYSICS · Single correct · CBSE · Physics · Current Electricity · Current Electricity
Problem
A student assumes that current I3 leaves a junction and calculates I3=−0.70A. Which of the following best explains the physical meaning of the negative sign?
(a) No current flows in branch 3 because a negative current value is not physically possible.
(b) The magnitude of the current is 0.70A and it still leaves the junction in the assumed direction.
(c) A current of 0.70A actually enters the junction rather than leaving as originally assumed.
(d) The negative sign means electrons, rather than positive charge, move away from the junction with 0.70A of current, so the original direction is still correct.