Question

The voltage across the $10\Omega$ resistor in the given circuit is $x$ volt.

The value of $x$ to the nearest integer is .

Answer 1

$50$ $\Omega$ and $20$ $\Omega$ are in parallel combination. Their equivalent resistance,

$R_{eq}=\frac{50\times 20}{50+20}$$\Rightarrow R_{eq}=\frac{1000}{70}=\frac{100}{7}\Omega$
These both resistances are in series combination, their equivalent resistance, $R_{eq}=10+\frac{100}{7}=\frac{170}{7}\Omega$

$I=\frac{V}{R}=\frac{170}{170/7}$
$I=7\text{A}$
$7\text{A}$ current will flow through $10\Omega$ resistor.
Potential Across $10$ $\Omega$:
$V_{10}=IR=7\times 10=70\text{V}$