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ChemistryMediumNumerical2021 ยท 01 Sep Shift 2

Q52.A 50 watt bulb emits monochromatic red light of wavelength of 795 nm. The number of photons emitted per second by the bulb is ๐‘ฅร— 1020 . The value of ๐‘ฅ is _____ . (Nearest integer) [Given : h = 6 . 63 ร— 10-34Js and ๐‘= 3 . 0 ร— 108 ms-1

What This Question Tests

This question involves calculating the energy of a single photon from its wavelength and then determining the total number of photons emitted per second by a light bulb of given power.

Concepts Tested

Energy of a photonPlanck's constantPower of light source

Formulas Used

E = hc/ฮป

Power = (Number of photons per second) * E

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