Question

An electron, a proton, a deuteron and an alpha particle are all accelerated from rest through the same potential difference. Which one will have the maximumde Broglie wavelength?

Options

• Proton

• Deuteron

• Electron

• Alpha particle

Answer 1

Electron

Explanation:

When a particle is accelerated through a potential difference (V), its de Broglie wavelength (λ) is calculated using:

λ = `h/p` = `h/sqrt(2 m q V)`

Since h (Planck’s constant) and V (potential difference) are the same for all the particles, the wavelength is inversely proportional to the square root of the product of mass (m) and charge (q):

`λ ∝ 1/sqrt(m q)`