Question

select all the correct answers. janet installed a dimmer on the lights in her bedroom. she slid the dimmer switch up, causing the resistance in the circuit to decrease. assuming the voltage is constant, what effect will janets actions have on the circuit? the voltage will increase from 120 to 240 volts. the lights will brighten. the current will decrease. the current will increase. the lights will dim.

Explanation:

Step1: Recall Ohm's Law

$I=\frac{V}{R}$, where $I$ is current, $V$ is voltage and $R$ is resistance.

Step2: Analyze effect of resistance decrease

As resistance $R$ decreases and voltage $V$ is constant, according to $I = \frac{V}{R}$, the current $I$ will increase.

Step3: Analyze effect on light brightness

More current means more power ($P = VI$) dissipated in the light - bulb, so the lights will brighten.

Answer:

The current will increase.
The lights will brighten.