Using the test results, reason for the higher amperage reading in bulb D compared to A and B?

Using the test results, reason for the higher amperage reading in bulb D compared to A and B?

• A. Bulb D is newer
• B. Lower resistance in bulb D
• C. Higher voltage across D
• D. Longer wire in bulb D

Answer: (B)

When voltage is the same across each bulb, the current through a bulb depends on its resistance according to I = V / R. If bulb D shows a higher current than A and B, its resistance must be lower at the moment of the test. That reduced resistance lets more current flow through D under the same supply voltage. In bulbs, resistance changes with temperature as the filament heats up; a bulb with a lower operating resistance will draw more current. If these bulbs are in parallel, each sees the same voltage, so differences in current reflect differences in resistance. Other factors like being newer or longer wire would not naturally explain a higher current in D at the same voltage, since longer wires raise resistance and newer bulbs aren’t guaranteed to have lower resistance.

When voltage is the same across each bulb, the current through a bulb depends on its resistance according to I = V / R. If bulb D shows a higher current than A and B, its resistance must be lower at the moment of the test. That reduced resistance lets more current flow through D under the same supply voltage. In bulbs, resistance changes with temperature as the filament heats up; a bulb with a lower operating resistance will draw more current. If these bulbs are in parallel, each sees the same voltage, so differences in current reflect differences in resistance. Other factors like being newer or longer wire would not naturally explain a higher current in D at the same voltage, since longer wires raise resistance and newer bulbs aren’t guaranteed to have lower resistance.