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Quantum theory — Question 278

Original QCE Vault practice · 3 marks

Q278 · Practice questionComplex familiar3 marks

QUESTION 278 (3 marks)

An electron in an allowed Bohr orbit satisfies

n\lambda=2\pi r

and

p=h/\lambda

. Treat its momentum as nonrelativistic.

a)

Show algebraically that these two relations imply

mvr=nh/(2\pi)

.

[2 marks]

b)

For

n=2

and

r=2.12\times10^{-10}\,\mathrm m

, calculate the wavelength.

[1 mark]

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