A Red Laser Pointer Emits Light at a Wavelength of 488

question 31

Multiple Choice

A red laser pointer emits light at a wavelength of 488 nm.If the laser emits 7.5 $\times$ 10^-4 J of energy per second in the form of visible radiation,how many photons per second are emitted from the laser?

• A) 4.1 \(\times\) 10^-19 photons/sec
• B) 5.4 \(\times\) 10^-16 photons/sec
• C) 8.9 \(\times\) 10¹⁴ photons/sec
• D) 1.8 \(\times\) 10¹⁵ photons/sec
• E) 2.5 \(\times\) 10¹⁸ photons/sec

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Definitions:

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