- A Light Bulbs And Circuit Combinations A1 Connect A Single Bulb To The Power Supply And Fix A Nonzero Voltage The Bul 1 (166.48 KiB) Viewed 9 times
A. Light bulbs and Circuit Combinations A1. Connect a single bulb to the power supply and fix a nonzero voltage. The bulb should shine. You can think of a bulb as acting similarly to a resistor, where the bulb's brightness is proportional to power P-12R. Changing the applied voltage changes the current running through the bulb, and therefore the power, and therefore the brightness. Try changing the voltage on the power supply in order to verify thigs behavior. Next, keep the voltage fixed and add a second bulb first in series, then in parallel, with the first bulb. Compare the bulbs in the three situations in terms of brightness. A2. Write a ranking of the brightness on your whiteboard, and include a qualitative explanation in terms of currents, voltages, and resistances. E.g. which quantities are fixed? Which change? Why? A3. Now add a third bulb to the series combination, like so: DC Power Supply Bulb 1 Wire Bulb 2 Wire Bulb 3 A4. Rank the brightness of bulbs including before and after the addition of the resistor and see if your group can explain the observed effects qualitatively. Write out the ranking and explanation on your whiteboard as you did with the other circuits.