(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Estimate how many photons of visible light (500 nm) are emitted by a 100 W Bulb.

The answer on the sheet says approximately 10[itex]^{20}[/itex] photons/second

However when I work it out I get a slightly different answer.

2. Relevant equations

I used that 1J=1W/s or E=P/t

Also Energy of one photon is E=hf so if you had lots of photons you would [itex]\Delta[/itex]E=nhf where n is the number of photons.

3. The attempt at a solution

I get 2.5[itex]\times[/itex]10[itex]^{20}[/itex] photons/second

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# Photons/Second from a 100W bulb.

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