Question

The speed of three particles is recorded as 3 m/s, 4 m/s, and 5 m/s. What is a root mean square speed of these particles?

(a) 4.082 m/s

(b) 2.07 m/s

(c) 3.87 m/s

(d) 3.082 m/s

I have been asked this question in an online quiz.

This interesting question is from States of Matter in portion States of Matter of Chemistry – Class 11

Answer 1

Correct answer is (a) 4.082 m/s

Best explanation: The root means square speed of particles is nothing but the square root over the sum of squares of the particle’s speeds by a total number of particles. So by substituting, √3^2 + 4^2 + 5^2/3 = 4.082 m/s.