Question

if youve already done this activity and want to try again (untracked), feel free to replay activity no task tracking you can resize the interactive by slowly dragging the dashed lines to the right of the interactive. you may also click the full screen icon on the top left to go full screen if possible on your device. having problems staying logged in or are you experiencing issues? please visit our troubleshooting section for solutions. mission ec4: resistance, voltage and current a certain electrical circuit contains a battery, wires and a light bulb. which of the following would cause the bulb to shine less brightly? identify all that apply. a. increase the voltage of the battery b. decrease the voltage of the battery c. increase the resistance of the circuit d. decrease the resistance of the circuit e. open the circuit

Explanation:

Step1: Relate brightness to power

The brightness of the bulb depends on the power it dissipates, given by $P = \frac{V^2}{R}$ (where $V$ is voltage across the bulb, $R$ is circuit resistance) or $P=I^2R$ (where $I$ is current). Lower power means dimmer light.

Step2: Analyze option a

Increasing battery voltage ($V$) increases $P = \frac{V^2}{R}$, so bulb gets brighter. Eliminated.

Step3: Analyze option b

Decreasing battery voltage ($V$) decreases $P = \frac{V^2}{R}$, so bulb dims. Valid.

Step4: Analyze option c

Increasing circuit resistance ($R$) decreases current $I=\frac{V}{R}$, so $P=I^2R$ decreases. Bulb dims. Valid.

Step5: Analyze option d

Decreasing circuit resistance ($R$) increases current $I=\frac{V}{R}$, so $P=I^2R$ increases. Bulb gets brighter. Eliminated.

Step6: Analyze option e

Opening the circuit stops current flow ($I=0$), so $P=0$ and the bulb turns off (which is less bright than glowing). Valid.

Answer:

b. decrease the voltage of the battery, c. increase the resistance of the circuit, e. open the circuit