question_answer

Which of the plots shown in the figure represents speed (v) of the electron in a hydrogen atom as a function of the principal quantum number (n)? [JEE ONLINE 26-05-2012]

A) B

B) D

C) C

D) A

Correct Answer: A

Solution :

[a] Velocity of electron in  orbit of hydrogen atom is given by:

Substituting the values we get,

or

As principal quantum number increases, velocity decreases.