Answer
$117\;V$.
Work Step by Step
Voltage drop $\propto$ resistance.
Let the required voltage drop is $x$.
we can write.
$\Rightarrow \frac{28\;\Omega}{52\;V}=\frac{63\;\Omega}{x}$
Cross multiply.
$\Rightarrow 28\times x=63\times 52$
Divide both sides by $28$.
$\Rightarrow x=\frac{63\times 52}{28}$
Simplify.
$\Rightarrow x=117$.
