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A discharge lamp rated at 25 W (1 W = 1 J/s) emits yellow light of wavelength 580 nm. How many photons of yellow light does the lamp generate in 1.0 s?

User Shaquira
by
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1 Answer

5 votes

Answer:

the number of photons of yellow light does the lamp generate in 1.0 s is 7 x
10^(19)

Step-by-step explanation:

given information:

power, P = 25 W

wavelength. λ - 580 nm = 5.80 x
10^(-7) m

time, t = 1 s

to calculate the number of photon(N), we use the following equation

N = λPt/hc

where

λ = wavelength (m)

P = power (W)

t = time interval (s)

h = Planck's constant (6.23 x
10^(-34) Js)

c = light's velocity (3 x
10^(8) m/s^(2))

So,

N = λPt/hc

= (5.80 x
10^(-7))(25)(1)/(6.23 x
10^(-34))(3 x
10^(8) m/s^(2))

= 7 x
10^(19)

User Koes Bong
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