[tortoise]

An  incandescent  light bulb  functions because of  the  flow of electric current. Does the incandescent light bulb convert  all of  the electrical energy  to  light? Observe  a  functioning  incandescent  light  bulb,  and  explain what  occurs with reference to the Law of Conservation of Energy?

First, I think it doesn't.
Second, I don't understand the question clearly. I think the Law of Conservation of Energy is right in this case (of course, it's right in all of the cases  ). So, help me to answer the second question.

Thanks in advance.

[ARGOS++]

Dear Tortoise,

Of course!, you are right, that it's right in all of the cases !!

But a simple Question: Did you ever touch a burning conventional light bulb with your “naked” fingers? What did you feel?
Of course - heat! I think also you would say that’s a kind of energy, and it’s different to light!

So, how is the conventional light bulb working?
The energy of the current will be converted to heat and rises the temperature of the wire helix.
Above a certain temperature the helix will radiate some of the energy in the visible region of the spectrum, and you will recognise it as light!
Quintessence:   Only a small amount of the energy is converted to light, and most of it is still converted to heat!

For conventional light bulbs the conversion factor to light is about ~8%.
For fluorescence light bulbs the conversion factor to light is about ~18 till ~28%.
Better!  -  But: Still an immense lost of energy!!


Good Luck!
                    ARGOS⁺⁺

[tortoise]

Thank you very much, ARGOS++ ! 

But, "energy cannot be created or destroy in a chemical reaction or
a physical change. It can only connverted from one to
another". Can you tell why is there an immense lost of energy?

[ARGOS++]

Dear Tortoise,

I BEG Your pardon!, that I have animated you to do an error in reasoning!

Of course!, You’re absolutely right!  -
My “Still an immense lost of energy!!” is not violating the initial law, as it has a different meaning.

As you now may know, that a conventional light bulb is “producing” only ~8% of Light, but ~92% of Heat out of 100% electric power, it should mean a “lost” in the sense of a real “WAIST” of so much energy in the wrong direction!
Maybe you can spend an additional thought about my noted Quintessence again.

So I hope it is coming clearer now.
Sorry once again.

Good Luck!
                    ARGOS⁺⁺