Posted by Jazmin on Sunday, October 31, 2010 at 10:41pm.
Suppose you have a 10 watt fluorescent light bulb. If this light bulb is 6 % efficient in turning electricity into light, then how many photons are being emitted per second? Assume that average energy of all the photons emitted is 550 nm, thus you can treat all the photons as having the same energy as a 550 nm photon. Lastly, 1 watt = 1J/s
this is my answer
1.66E17
can you please tell me if i did it right
thank you

chemistrycheck answer  DrBob222, Sunday, October 31, 2010 at 11:05pm
I have 1.66E18.
10 watt bulb @ 6% = 10*0.06 = 0.6 watt = 0.6 J/s. (I suspect we differ here.)
I used 6.626E34 for h.
I used 3E8 for c.
I used 550E9 for the wavelength.
This gave E = 3.61E19
Then 0.6 J x 1 photon/3.61E19 J =