The sum of the currents into a junction equals the sum of th

\"The sum of the currents into a junction equals the sum of the currents out of the junction\" is a consequent of: Newton\'s third law Ohm\'s law Newton\'s second law conservation of energy conservation of charge

Solution

It is a consequence of conservation of charge. Because the current in a juntion is conserved means the the charge is conserved. Current=charge/time. So at each time the charge conservation produces the current conservation as thejunction needs to be electrically neutral.