Molecule Kinetics: Calculating Temperature from Speed Upon Moon Re-Entry

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Homework Statement



A space vehicle returning from the Moon enters Earth’s atmosphere at a speed of about 4.9E4 km/h. Molecules (assum nitrogen) striking the nose of the vehicle with this speed correspond to what temperature?

Homework Equations



KE=0.5mv^2=kT
k: constant

The Attempt at a Solution



I'm lost.
 

Discussion

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Dick said:
Look up the mass of an N2 molecule and Boltzmann's constant, k, put them into your first equation and solve for T. ?

Can't look up mass, only molecular weight. Where mass=#mols*molecular weight.
 
bpw91284 said:
Can't look up mass, only molecular weight. Where mass=#mols*molecular weight.

You can so look up the mass of a single nitrogen atom. It's in the periodic table in atomic mass units. What's an atomic mass unit in kilograms? Can also be looked up.
 
Dick said:
You can so look up the mass of a single nitrogen atom. It's in the periodic table in atomic mass units. What's an atomic mass unit in kilograms? Can also be looked up.

N=14.00674u
1 u ≈ 1.66053886 × 10−27 kg

Then just solve for T with 0.5mv^2=kT?

Thanks,
Brandon