Question

For the same kinetic energy, the momentum shall be maximum for which of the following particle?

• A. Electron
• B. Proton
• C. Deuteron
• D. Alpha particle

Answer 1

Answer: (D)

Alpha particle

we know that kinetic energy($k$) and momentum($p$) are related as

$k=\frac{p^2}{2m}$

$\therefore momentum\left(p\right)=\sqrt{2mk}p\propto \sqrt{m}$

Since alpha particle has higher mass than electron, proton and deuteron, its momentum will be maximum.