If a second lamp is added in parallel, what happens to the voltage across each lamp?

If a second lamp is added in parallel, what happens to the voltage across each lamp?

• A. Drops to half
• B. Remains the same as the cell voltage
• C. Doubles
• D. Becomes zero

Answer: (B)

In a parallel circuit, every branch experiences the same voltage as the source. Adding a second lamp in parallel does not change the voltage across each lamp; it stays equal to the cell voltage. Only the total current drawn from the cell increases because there are two paths for current. (With a non-ideal source, there could be a tiny drop due to internal resistance, but in standard problems it remains the same.)

In a parallel circuit, every branch experiences the same voltage as the source. Adding a second lamp in parallel does not change the voltage across each lamp; it stays equal to the cell voltage. Only the total current drawn from the cell increases because there are two paths for current. (With a non-ideal source, there could be a tiny drop due to internal resistance, but in standard problems it remains the same.)