Question

From the fig. calculate

(i) Total resistance of the circuit

(ii) Value of ‘R’

(iii) Current flowing through R

If Ammeter reads (0.3A)

• A. 20Ω; 30Ω; 0.1A
• B. 30; 20; 0.1A
• C. 20; 20; 1A
• D. can’t decide (insufficient data)

Answer 1

The correct option is A

20Ω; 30Ω; 0.1A

R_total = $\frac{V}{i}$ = $\frac{6}{0.3}$ = 20 Ω

$\frac{1}{20}$ = $\frac{1}{30}$ + $\frac{1}{R}$

• R = 30 Ω

$i_1$ = 0.2A

Now,$\frac{i1}{i2}$= $\frac{60}{30}$ = 2

• $i_2$ = 0.1 A