Assume that I have Bulb that consumes 10 watts of electrical energy (power). The operating values for full brightness are: 5 volts, and 2 amps. Since Power(p) = Voltage(V) x Current(I) = 5 x 2 = 10 watts
For a bulb to glow all it cares for is the flow of electrons at the required rate (amps) --> call it axiom. In the above circuit, assume that I keep the current constant at 2 amps by reducing both the voltage and resistance.
So, by my axiom, I expect the same brightness of the bulb, but the bulb glows at lower brightness. I know the lower brightness is because of lower power since voltage is reduced, but by my axiom: "For a bulb to glow all it cares for is the flow of electrons at the required rate (amps)", shouldn't the bulb remain bright?
Or, is my axiom wrong?
Edit: As many of you have mentined, I accept that usage of the word axiom is wrong in this context. I would rather use the word assumption, however, since many answers to this questions refers to the word axiom, I do not want to change it to assumption, as this would confuse future readers. Thanks.