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Calculate the number of photons emitted in `10` hours by a `60 W` sodium lamp (`lambda` of photon `= 5893 Å)` |
Answer» Energy emitted by sodium lamp in 1 sec = `"watt" xx"sec"=60xx1=60 J`. Energy of photons emitted (E) = `hv=hc//lambda` `=((6.626xx10^(-34)Js)xx(3xx10^(8)ms^(-1)))/((5893xx10^(-10)m))=3.37xx10^(-19)J`. No. of photon emitted per second `=("Energy emitted in 1s")/("Energy of one photon")=((60J))/((3.37xx10^(-19)J))=1.78xx10^(20)`. No. of photons emitted in 10 hrs= `1.78xx10^(20)xx10xx60xx60=6.41xx10^(24)`. |
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