CBSE Class 10 Science 2019 · Paper 31/1/3/C · Question 7

Electricity 3 marks Medium

In the given circuit, find :

Answer

The resistance is $6 Ω$ , the ammeter reads $1$ A, and there is $3$ V across the $3 Ω$ resistor and across the $6 Ω$ pair.

(a) The two

6 Ω

resistors are in parallel:

\frac{1}{R _{p}} = \frac{1}{6} + \frac{1}{6}

, so

R_{p} = 3 Ω

. This is in series with

3 Ω

, so the total resistance is

R = 3 + 3 = 6 Ω

. (b) Current through the ammeter:

I = \frac{V}{R} = \frac{6}{6} = 1

A. (c) Potential difference across the

3 Ω

resistor

= 1 \times 3 = 3

V; potential difference across the

6 Ω

resistors

= 1 \times 3 = 3

V, the same

3

V across each, with

0.5

A through each.

🔒 Step-by-step solution