Five molecules of a gas have the following speeds:
200 m/s,
300 m/s,
400 m/s,
500 m/s, and
600 m/s.
The rms speed for these molecules is
A) 300 m/s
B) 344 m/s
C) 400 m/s
D) 424 m/s
E) 534 m/s

Question

Quizplus · Accepted Answer

The formula for rms speed is:
v_rms = √( (v_1^2 + v_2^2 + ... + v_n^2) / n )
Plugging in the given values:
v_rms = √( (200^2 + 300^2 + 400^2 + 500^2 + 600^2) / 5 )
v_rms ≈ 424 m/s
Therefore, the best choice is D.

Five Molecules of a Gas Have the Following Speeds