Question

Why must the amount of charge entering a junction per second equal the amount leaving when current is steady?

Options

• The emf supplied by a cell is zero

• Charge does not accumulate at any junction

• Potential depends only on current

• The resistance of each branch is equal

Answer 1

When the current is steady, charge does not accumulate at a junction. Therefore, charge entering per second must equal charge leaving per second, giving KCL.