As one turns on more lamps in an ordinary household circuit, will the current in the first lamp be affecte? Wh

Question

As one turns on more lamps in an ordinary household circuit, will the current in the first lamp be affected? What will happen to the line current? To the line voltage? Why is it not customary to connect household electric lamp in series?

Answer 1

appliances are connected in parallel, which means they each get the full 120 volts applied (240 in europe). And that means their current does not change as other appliances are turned off and on.

Series is not used because of the problem you just stated, the current and voltage would change each time you switched a different applicance on or off.

Answer 2

The lamps are connected in parallel, so in theory the current should remain the same.  If lamps were connected in series, then the only way to have one on is to have ALL of them on.  Turning off one lamp would stop the flow of current in the series circuit and all lamps would go out.

In the real world there will be a voltage drop whenever current is flowing.  From the utility transformer through the service drop cable into the main panel and even through the wires in your home.  As you turn on more and more lamps, the load will increase and the voltage will decrease.  Since the lamps have a fixed resistance, as the voltage decreases, the current will be reduced.  The current to the first lamp will go down as more and more laps are connected.

Answer 3

If we ignore the very, very small increase in voltage drop across the line resistance caused by the increase in line current then, as we turn on more lamps the current in the first lamp will remain the same, the line current will increase and the line voltage will remain the same.

It is not practical to operate household electrical lamps in series. If any one of the lamp filaments burns open then all of the lamps goes off. The current through the lamps would decrease each time you added a lamp to the circuit. Decreasing the current would decrease the luminance of each lamp. Individual lamp luminance would change each time you added or removed a lamp.