Question

Reading of ammeter is 1 A. If each of the 4 Ω resistor is replaced by 2 Ω resistor, the reading of ammeter will become nearly –

• A. 1 .11 A
• B. 1.25 A
• C. 1.34 A
• D. 1.68 A

Answer 1

Answer: (A)

1 .11 A

Answer 2

If r_A = Ammeter resistance

then 1 A = $\frac{10V}{R_{eq}}$ = $\frac{10}{9 + r_{A}}$⇒ r_A = 1Ω

So Now I = $\frac{10}{8 + 1}$ = $\frac{10}{9}$A = 1.11 A