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
1 answer:
Answer:
the number of photons of yellow light does the lamp generate in 1.0 s is 7 x
Explanation:
given information:
power, P = 25 W
wavelength. λ - 580 nm = 5.80 x 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 Js)
c = light's velocity (3 x )
So,
N = λPt/hc
= (5.80 x )(25)(1)/(6.23 x
)(3 x
)
= 7 x
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Answer:
The rate of heat conduction through the layer of still air is 517.4 W
Explanation:
Given:
Thickness of the still air layer (L) = 1 mm
Area of the still air = 1 m
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To determine the rate of heat conduction through the still air, we apply the formula below.
Q = 517.4 W
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