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1 year ago

An electon in a box absorbs light. The longest wavelength in the absorbtion spectrum is 700 nm . How long is the box

Physics

1 answer:

vova2212 [387]1 year ago

4 0

Answer:

8.01 (10^-10) m

Explanation:

use the Particle in a box equation

E = (n^2) (h^2) / (8 m (L^2))

and energy of a particle as its wavelength equation

h c / lamda = E

combine the equations to get

h c / lamda = (n^2) (h^2) / (8 m (L^2))

get L alone

L^2 = (2^2 - 1^2) h lamda / 8 m c

the longest wavelength is produced by a jump from the first excited state to the ground so

n = 2 to n = 1

L^2 = (n1^2 - n2^2) h lamda / (8 m c)

h = 6.6(10^-34) J*s

c = 3(10^8) m/s

m = 9(10^-31) kg

lamda = 700(10^-9) m

n1 =2

n2=1

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$0.3\times10^{-2}=\dfrac{5\times\lambda}{1.2\times10^{-3}}$

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2 years ago

When a condenser discharges electricity, the instantaneous rate of change of the voltage is proportional to the voltage in the c

e-lub [12.9K]

Answer:

460.52 s

Explanation:

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dV/V = kdt

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∫dV/V = ∫kdt

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3 years ago

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