Resistances R1 , R2 , R3 and R4 are connected as shown in the figure.

1.	Resistances R1 , R2 , R3 and R4 are connected as shown in the figure. S1 and S2 are two keys. Discuss the current flowing in the circuit in the following cases.a. Both S1 and S2 are closed. b. Both S1 and S2 are open. c. S1 is closed but S2 is open.
Answer» (a) When both S₁ and S₂ are dosed, the effective resistance of the circuit decreases and hence, current will increase. (b) When both S₁ and S₂ are open, the effective resistance of the circuit increases and hence, current will decrease. (c) When S₁ is closed and S₂ is open, the effective resistance of the circuit decreases and hence current will increase. [Current will be more than case (b) but less than in case (a)]

Resistances R1 , R2 , R3 and R4 are connected as shown in the figure. S1 and S2 are two keys. Discuss the current flowing in the circuit in the following cases.a. Both S1 and S2 are closed. b. Both S1 and S2 are open. c. S1 is closed but S2 is open.

Answer»

(a) When both S₁ and S₂ are dosed, the effective resistance of the circuit decreases and hence, current will increase.

(b) When both S₁ and S₂ are open, the effective resistance of the circuit increases and hence, current will decrease.

[Current will be more than case (b) but less than in case (a)]