Answer:
4 A
Explanation:
The relationship between current, voltage and resistance in a circuit is given by Ohm's law:
[tex]V=RI[/tex]
where
V is the voltage
R is the resistance
I is the current
The equation can also be rewritten as
[tex]I=\frac{V}{R}[/tex]
from which we see that the current is inversely proportional to the resistance, R.
In this problem, the initial current is I = 8 A. Then the resistance is doubled:
R ' = 2R
So the new current is
[tex]I'=\frac{V}{R'}=\frac{V}{2R}=\frac{1}{2}(\frac{V}{R})=\frac{I}{2}=4 A[/tex]
so the current is halved.
