Question

A tube light converts electrical energy into heat energy A. True B. False

Answer 1

Hint: The basic idea of the energy in the field of physics is to be versatile and compatible in use. The reason that energy can be so easily converted from one form to another is due to the fact, energy is a conserved quantity. In physics, the conserved quantity of a system is a function of the dependent variables of the system which remain constant irrespective of the path the system takes or the time elapsed.
Electricity is the most effective and versatile form of energy because it can be easily converted into mechanical energy, heat, sound, and light energy etc.

Complete step by step answer:
Since energy is conserved, the fundamental law of conservation of energy says that energy can neither be created nor destroyed but can be converted from one form to another. Thus, the net energy of the universe remains constant and conserved.
Before, we understand the specifics of energy conversion in a tube light, let us see what a tube light consists of, and its working.
The tubelight is the commercial name for the linear fluorescent lamp.
The fluorescent tube consists of mercury vapour mixed with inert gases like neon, argon, and krypton at low pressure.
When the electric current is passed through the tube, the electron collides with an atom of mercury. This collision of the electron with the atom of mercury excites the electrons to a higher state and when they return to their original state, they emit light energy in the form of photons. This phenomenon of emission of light is called fluorescence.
Thus, the electricity is converted to light energy and not heat energy.
Hence, the statement in the question is Option B – False.

Note: This statement cannot entirely be true, since very low amount of heat energy does gets out of the tube light if it is switched on for a longer time and the heat energy is dependent on current and resistance of the tube light in a relation as explained by Joule’s law of heating.
Heat energy, $H={{I}^{2}}Rt$ where $I$ is current and R is resistance and t is the time.