Why Does the Tube Light in My House Use So Much Voltage?!

You have very weak power. When you turn one appliance on, it is dropping the voltage to the rest of your system. Everything else is burning up more slowly, but the"'tube light" (assuming a fluorescent lamp) just ceases to function correctly. It has a transformer to facilitate ignition inside the lamp by controlling the current flow, a device called a "ballast". Any deviation from the rated voltage will cause the ballast to shut down rather than let the lamp go uncontrolled (which would destroy it), then the "start circuit" of the fixture fires again and again trying to re-light it. As long as there is insufficient voltage, it will continue like this until something burns up.

Interesting tutorial on fluorescent lamps.

"tube light" - Are you referring to a fluorescent fixture?

If so, two possible answers - could be the ballast voltage tolerance (voltage -/+) is very tight or your incoming utility service is on the lower side of the utility specified voltage.

It is not necessarily a mater of your fixture "using so much voltage" but more a case of your fixture not receiving enough voltage.

tube light is discharge lamp it need more voltage to light up, bcoz electrons need more potential to move one electrode to onther.