An electron is accelerated through a potential difference of $100\,V$. Its de Broglie wavelength is approximately
A$1.23\,Å$
B$12.3\,Å$
C$0.0123\,Å$
D$0.123\,Å$
Answer & Solution
Correct answer: A. $1.23\,Å$
For an electron accelerated through $V$ volts, $\lambda = \dfrac{12.27}{\sqrt{V}}\,Å$. With $V = 100$: $\lambda = 12.27/10 \approx 1.23\,Å$. This is comparable to atomic spacings — basis of electron diffraction.
Related questions
Calcium-40 (Z=20, A=40) and Argon-40 (Z=18, A=40) are best described as:Atoms of the SAME element with DIFFERENT mass numbers are called:An atom of chlorine has atomic number Z = 17 and mass number A = 37. The number of neutronThe atomic number (Z) of an element is equal to the:The neutron was discovered by:Bohr's model of the atom fixed Rutherford's instability problem by proposing that electronRutherford's gold foil experiment concluded that most of the atom is:The Rydberg constant for hydrogen, in SI units, is