Answer:
Resistance become infinite
Explanation:
In series circuit when switch is closed then a current is flow which is equal to [tex]\frac{V}{R}[/tex], here V is voltage and R is resistance
But when switch is open then no current is flow in the circuit
So [tex]\frac{V}{R}=0[/tex], this is possible when resistance become infinite
So when switch is open then resistance of the circuit will become infinite
