Ohm's law states that the potential difference across a resistor is directly proportional to the current flowing through it:
[tex]V=IR[/tex]
where
V is the potential difference
I is the current
R is the resistor
In our problem, the potential difference is the voltage of the battery, V=20 V, and the current flowing in the light bulb is I=0.57 A. By using Ohm's law, we can calculate the resistance of the light bulb:
[tex]R= \frac{V}{I}= \frac{20 V}{0.57 A}=35.1 \Omega [/tex]
