Question

In the circuit shown in Fig, the current I has a value equal to

• A. 1A
• B. 2A
• C. 4A
• D. 3.5A

Answer 1

The correct option is A 1A

The equivalent resistances of each combinations,

For 15 ohm resistances in parallel

$R_{eq1}=\frac{15}{3}=5\Omega$

For 4 ohm resistances in parallel

$R_{eq2}=\frac{4}{2}=2\Omega$

Hence the current through circuit is

$I=\frac{E}{R_{eq1}+R_{eq2}+2+r}$

$I=\frac{10}{5+2+2+1}=1$ A