De Broglie Hypothesis

The de Broglie wavelength of a particle is given by the formula:

where:

• is the Planck's constant,
• is the mass of the electron,
• is the velocity of the electron,

Substitute these values into the formula:

Calculate the denominator:

Now calculate the de Broglie wavelength:

Thus, the de Broglie wavelength of the electron is approximately , which corresponds to the first option given.