de Broglie Wavelength — Practice Quiz

Question 1

de Broglie wavelength of an electron accelerated through 100 V:

Accepted Answer

1.23 Å

Answer

0.123 Å

Answer

12.3 Å

Answer

0.0123 Å

Question 2

An electron has K = 200 eV. Its de Broglie wavelength:

Accepted Answer

≈ 0.87 Å

Answer

≈ 0.5 Å

Answer

≈ 1 Å

Answer

≈ 0.1 Å

Question 3

If an electron and a proton have the same KE, the ratio λ_e/λ_p is:

Accepted Answer

√(m_p/m_e) ≈ 42.8

Answer

m_p/m_e ≈ 1836

Answer

m_e/m_p

Answer

1

Question 4

A particle of mass 1 g moves at 1 m/s. Its de Broglie wavelength:

Accepted Answer

~10⁻³⁰ m

Answer

~10⁻²² m

Answer

~10⁻³⁴ m

Answer

Can't compute

Question 5

When the velocity of an electron is doubled, its de Broglie wavelength:

Accepted Answer

Halves

Answer

Doubles

Answer

Quadruples

Answer

Stays the same