Answer:
Option D
Explanation:
Given, kinetic energy of electron =5.5 eV
The energy required to excite a hydrogen atom from ground state (n=1) to first excited state (n=2) is
$\triangle E= E_{2}-E_{1}$
= -3.4-(-13.6)=10.2 eV
When an electron collids with hydrogen atom in the ground state with energy of 5.5 eV which is less than 10.2 eV , then it will not be able to excite hydrogen atom into first excited state. Therefore, electron will not give any energy to the hydrogen atom. Gence , the total kinetic energy of electron remains conserved . Hence , its collision with hydrogen atom is elastic
