How many photons are incident on the skin

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One of the first signs of sunburn is the reddening of the skin (called erythema). As a very rough rule of thumb, erythema occurs if 16 mJ of ultraviolet light of approximately 297-nm wavelength (referred to as UVB radiation) is incident on the skin per square centimeter during a single exposure. How many photons are incident on the skin in this amount of exposure?

Reference no: EM13318405

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