# A singly ionized 'He' ion and 'H' ion are accelerated from rest through a potential difference 'V' to velocities 'U(He)' and 'U(H)' respectively. What is the ratio of 'U(He)/U(H)'?

##### 1 Answer

Jun 30, 2018

#### Answer:

#u_(He)/u_(H) = 1/2#

#### Explanation:

For each ion that means:

As

#u_(He)/u_(H) = sqrt( m_H/m_(He) ) = sqrt((1" u")/(4 " u")) = 1/2#

[Approx mass figures used, and assumed non-relativistic]