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myrzilka [38]
3 years ago
7

An electron is confined to a one dimensional region, bounded by an infinite potential. If the energy of the electron in its firs

t excited state is 40 meV, what is its energy in its ground state? A. 40 me V B. 80 meV C. 20 meV D. O meV E. 10 meV
Physics
1 answer:
OLga [1]3 years ago
4 0

Answer:

The energy in its ground state is 10 meV.

Explanation:

It is given that,

The energy of the electron in its first excited state is 40 meV.

Energy of the electron in any state is given by :

E=\dfrac{n^2\pi^2h^2}{8mL^2}

For ground state, n = 1

E_1=\dfrac{\pi^2h^2}{8mL^2}.............(1)

For first excited state, n = 2

40=\dfrac{2^2\pi^2h^2}{8mL^2}.............(2)

Dividing equation (1) and (2), we get :

\dfrac{E_1}{40}=\dfrac{1}{4}

E_1=10\ meV

So, the energy in its ground state is 10 meV. Hence, this is the required solution.

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