Question

In the circuit diagram shown in Figure, find the current through the $1\Omega$ resistor.

Answer 1

Let take the voltage of upper-middle point to be $v$.

From the figure

looking at the voltage drop

$\frac{(v-10)-10}{2}+\frac{v-0}{2}+\frac{v-5}{1}=0$

or $v=\frac{30}{4}=\frac{15}{2}V$
current through the $1\Omega$ resistor is $i=\frac{v-5}{1}=\frac{15}{2}-10$

$=\frac{5}{2}A$