(adsbygoogle = window.adsbygoogle || []).push({}); 1. The mass of the deuterium molecule D2 is twice the mass of Hydrogen molecule H2. If the vibrational frequency of H2 is 1.35x10^14 Hz, what is the vibrational frequency of D2, assuming the "spring constant" of attracting forces is the same for two species? Answer in unit of Hz.

2. Relevant equations

f=(w)/(2pie)

w=sq root (k/m)

k=m(w^2)

w is phrased as omega

3. The attempt at a solution

H2 :

f=1.35x10^14

(f)(2pie)=w = 8.48x10^14

k=m(w^2)=7.19x10^29(m)

D2 :

f=? <--solve

m=2k=2(7.19x10^29)m=1.439x10^30(m)

k=7.19m

w=sq root (k/m) = sq root [( 7.19x10^29m)/1.439x10^30m)]=w=0.707

f = 0.707/2pie = 0.1125 Hz

check?

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# Homework Help: SHM - Molecules Vibration

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