A lamp draws 3 amperes of current and is connected to a 120 volt supply.
We are asked to find the resistance of the lamp.
Recall the Ohm's law is given by
[tex]V=IR[/tex]Where V is the voltage, I is current, and R is the resistance.
Re-arrange the equation for resistance
[tex]R=\frac{V}{I}[/tex]Substitute the given values
[tex]\begin{gathered} R=\frac{120}{3} \\ R=40\; \Omega \end{gathered}[/tex]Therefore, the resistance of the lamp is 40 ohms.