If a 90-W lightbulb emits 3.5 % of the input energy as visible light (average wavelength 550 nm) uniformly in all direct

Post by **answerhappygod** » Wed Jul 06, 2022 11:23 am

: If A 90 W Lightbulb Emits 3 5 Of The Input Energy As Visible Light Average Wavelength 550 Nm Uniformly In All Direct 1 (7.68 KiB) Viewed 19 times

: If A 90 W Lightbulb Emits 3 5 Of The Input Energy As Visible Light Average Wavelength 550 Nm Uniformly In All Direct 2 (7.96 KiB) Viewed 19 times

: If A 90 W Lightbulb Emits 3 5 Of The Input Energy As Visible Light Average Wavelength 550 Nm Uniformly In All Direct 3 (8.96 KiB) Viewed 19 times

If a 90-W lightbulb emits 3.5 % of the input energy as visible light (average wavelength 550 nm) uniformly in all directions.
How many photons per second of visible light will strike the pupil (4.0 mm diameter) of the eye of an observer 1.3 m away? Express your answer using two significant figures.
How many photons per second of visible light will strike the pupil (4.0 mm diameter) of the eye of an observer 1.3 km away? Express your answer using two significant figures.