## Question

A 100 watt butt bulb emits monochromatic length of wavelength 400 nm. Calculate the number of photons emitted per second by the bulb.

### Solution

Power of the bulb = 100 watt

= 100 J s^{–1}

Energy of one photon, *E = hv *

∴ Number of photons emitted

.

#### SIMILAR QUESTIONS

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