Question

Consider the circuit shown in the figure (32-E8). Find the current through the 10 Ω resistor when the switch S is (a) open (b) closed.
figure32-E8

Answer 1

Explanation:

(a) In a series, the resistors will be linked when S is open because there will be flow of current through 20 Ω resistor.

The effective resistance can be shown as  

$R_e_f_f$ = 10+20 Ω = 30 Ω

Through the circuit, the current flows. This can be shown as  

A = 0.1 A ; i = 330  

(b) There will be a flow of current via the switch when the switch S is closed. It can be seen that the current passes via this switch offering the slightest resistive path.

• So, in this case, the 20 Ω resistance will be unproductive. In this scenario, the effective resistance can be shown as $R_e_f_f$ = 10 Ω.
• Through the circuit, the current flows, so A = 0.3 A and i = 310.