What is the wavelength of an electron of 5eV energy?

In summary, the question asks for the wavelength of an electron with 5eV of energy. To solve this, de Broglie's equation must be used, which is lambda = h/p. However, using Planck's constant in eV does not work, and it needs to be converted to J/s. Additionally, the mass (m) may also need to be converted to eV. Other methods have multiplied 2mK by the electron charge to change J/s to eV, which has yielded the correct answer.
  • #1
ldc1
1
0

Homework Statement


Calculate the wavelength of an electron which has 5eV of energy.

Homework Equations


de Broglie's equation: lambda=h/p , kinetic energy equation: K=0.5mv^2

The Attempt at a Solution


My attempt: I figured out that using de Broglie's wavelength equation was necessary for this question. but after changing around everything to get lambda = h/(2mK)^1/2, I kept on getting an incorrect answer.
From comparing my methods to others I found that using Planck's constant's value in eV didn't work.
What I really want to know is if I have to change the mass(m) to eV.
The others had used Planck's constant's value in J/s and had multiplied the 2mK by the electron charge ( to change J/s to eV), and it had worked for them.
Why is this?
 
Physics news on Phys.org
  • #2
Take care with your units.
 

1. What is the definition of wavelength?

Wavelength is the distance between two consecutive peaks or troughs in a wave.

2. How is the wavelength of an electron measured?

The wavelength of an electron can be measured using a technique called electron diffraction, where a beam of electrons is passed through a thin material and the resulting diffraction pattern is analyzed to determine the electron's wavelength.

3. Can the wavelength of an electron be calculated using its energy?

Yes, the wavelength of an electron can be calculated using the de Broglie equation, which relates an object's wavelength to its momentum and mass. However, this equation only applies to particles with very small masses, such as electrons.

4. What is the significance of an electron's wavelength?

The wavelength of an electron is significant because it exhibits wave-particle duality, meaning it can behave both as a particle and a wave. This is important in understanding the behavior of matter at the atomic and subatomic level.

5. How does the energy of an electron affect its wavelength?

The energy of an electron is directly proportional to its wavelength. This means that as the energy of an electron increases, its wavelength decreases, and vice versa.

Similar threads

Wavelength = deBroglie Wavelength?
    • Introductory Physics Homework Help
Replies
11
Views
2K
Electrons impinging on a crystal
    • Introductory Physics Homework Help
Replies
3
Views
1K
Electron in a light microscope
    • Introductory Physics Homework Help
Replies
10
Views
455
Calculate the wavelength when electron transits.
    • Introductory Physics Homework Help
Replies
2
Views
787
Why does an electron have minimum kinetic energy when its momentum is 2h/λ?
    • Introductory Physics Homework Help
Replies
8
Views
1K
Beam current of positrons and electrons
    • Introductory Physics Homework Help
Replies
5
Views
1K
Wavelength-stopping potential dependence
    • Introductory Physics Homework Help
Replies
5
Views
1K
De Broglie wavelength of electron and proton
    • Introductory Physics Homework Help
Replies
14
Views
2K
The Total Energy of the Hydrogen Atom's Electron
    • Introductory Physics Homework Help
Replies
2
Views
836
Compare the wavelengths of a photon and an electron
    • Introductory Physics Homework Help
Replies
2
Views
2K

Hot Threads

Recent Insights

Back
Top