Question

In the figure given below, A, B and C are three ammeters. The ammeter B reads 0.5A. (All the ammeters have negligible resistance.)

Calculate:
(i) the readings in the ammeters A and C.
(ii) the total resistance of the circuit.

Answer 1

(i) P.d. across 6 Ω = P. d. across 3 Ω

Or 6 × 0.5 = 3 × i_c

Or i_c i.e., current passing through the ammeter C is:

`(6 xx 0.5)/3 = 1.0`ampere

(ii) Here, `1/"R" = 1/6 + 1/3 = 3/6 = 1/2`

or R = 2 Ω

∴ Total ressistance of the circuit = 2Ω + R = 2Ω + 2Ω = 4Ω

∴ Current through A = Current passing through B + current passing through C

= 0.5 + 1.0 = 1.5 ampere