Answer:
The least efficient light bulb is the first one (25 W - 210 Lumen)
Explanation:
Efficiency can be defined as what you want to obtain over what you need to produce it. In this case Eff= Wattage / Lumen. For each light bulb, their efficiency is: 8.4 / 11.12 / 15.7 Lum/W
The product of (wavelength) x (frequency) is always the same number ... the wave's speed.
So if the wavelength is somehow reduced to 1/4 its original length, the <em>frequency is immediately multiplied by 4</em> . That's the only way their product can remain the same.
Gave him good advice to others
No it does not! As it is not moving?!
