Question

Three resistors of $6.0\Omega ,2.0\Omega$ and $4.0\Omega$ are joined to an ammeter A and a cell of e.m.f. 6.0 V as shown in figure. The reading of ammeter is

• A. 2 A
• B. 1 A
• C. 0.6 A
• D. 4 A

Answer 1

The correct option is A 2 A

Combined resistance of $R_2$ and $R_3$ is given as $4+2=6$ ohms.

The total resistance in the circuit is given as :$\frac{1}{6}+\frac{1}{6}=\frac{1}{0.33}=3ohms$.
Hence, the effective resistance of the circuit is $3$ ohms.
The current in the circuit is calculated from the formula $I=V/R$.
That is, $I=\frac{V}{R}=\frac{6V}{3\Omega }=2A$.
Hence, the reading of ammeter is 2 A.