# Current on connecting wire

#### burgess

Help required to understand basic physics concept

Whether the current in connecting wire is more or less, compared with the current in the white hot filament of a common lamp? How can we find out?

Thanks

#### ChipB

PHF Helper
The current flowing through the filament is the same as the current in the connecting wires. Kirchoff's Current Law states that current flowing into a node of a circuit must equal the current flowing out. Think of electrical current as analogous to water flow - if you have a fat pipe (the connecting wire bringing current to the bulb) feeding into a skinny pipe (the filament) which is in turn is connected to another fat pipe (the return wire), the rate of water flow in gallons/minute is constant throughout all three pipes - the speed of the water may vary (speed of flow is higher in the skinny pipe) but the flow in terms of volume/time is constant. It has to be, or else water would be piling up someplace. Same principle applies heer - electric current must be constant through the wires and filament or else electrons would be piling up somewhere.

Last edited:

#### burgess

Excellent comparison!!! Simple explanations makes the subject easier!!! Thank you so much

The current flowing through the filament is the same as the current in the connecting wires. Kirchoff's Current Law states that current flowing into a node of a circuit must equal the current flowing out. Think of electrical current as analogous to water flow - if you have a fat pipe (the connecting wire bringing current to the bulb) feeding into a skinny pipe (the filament) which is in turn is connected to another fat pipe (the return wire), the rate of water flow in gallons/minute is constant throughout all three pipes - the speed of the water may vary (speed of flow is higher in the skinny pipe) but the flow in terms of volume/time is constant. It has to be, or else water would be piling up someplace. Same principle applies heer - electric current must be constant through the wires and filament or else electrons would be piling up somewhere.