Question

In a given circuit, each cell has an emf of $0.15\, V$ and internal resistance of $0.25 \, \Omega$ . Find the current in the circuit.

• A. 0.12 A
• B. 0.012 A
• C. 0.045 A
• D. 0.45 A

Answer 1

Answer: (C)

0.045 A

Answer 2

Number of cell $(n)=3$
Number of row $(m)=10$
Internal resistance $=0.25 \Omega$
$R=10 \,\Omega$
$E =0.15 V$
We know that,
$i=\frac{m n E}{n r+m R}$
$\Rightarrow i=\frac{10 \times 3 \times 0.15}{3 \times 0.25+10 \times 10}$
$\Rightarrow i=\frac{4.5}{0.75+100}$
$\Rightarrow i=\frac{4.5}{100.75}$
$\Rightarrow i=0.0446$
$\Rightarrow i=0.045\, A$