Question

Question 10
How many $176\Omega$ resistors (in parallel) are required to carry 5 A on a 220 V line?

Answer 1

For x number of resistors of resistance $176\Omega$, the equivalent resistance of the resistors connected in parallel is given by Ohm's law as V = IR
$R=\frac{V}{I}$
Where, supply voltage, V = 220 V
Current, I = 5 A
Equivalent resistance of the combination = R, given as
$\frac{1}{R}=x\times \left(\frac{1}{176}\right)$
$R=\frac{176}{x}$
From Ohm's law,
$\frac{V}{I}=\frac{176}{x}$
$x=\frac{176\times I}{V}=\frac{176\times 5}{220}=4$
Therefore, four resistors of $176\Omega$ are required to draw the given amount of current.