Electromagnetic radiation and quantum phenomena Flashcards
What is the threshold frequency?
The threshold frequency is the frequency which no electrons are emitted below it.
What is the formula for the energy emitted?
E = hf
What is planck constant?
It’s the constant of proportionality
What is intensity?
It’s the no.of photons arriving per second
What is the work function?
The energy needed to break the bonds holding the electrons down on a metal surface.
What is the equation for calculating threshold frequency?
F = work function / planck constant
What is Excitation?
The process of making the electron move up energy levels.
What vapour is inside a fluorescent tube?
Mercury
What is the electron volt defined as?
The electron volt is defined as the energy given to a fundamental charge, e, accelerated through a potential difference of 1 volt.
What does 1ev equal in joules?
1.6 x 10^-19 J
What is the ground state?
The lowest energy level
What quantum number does the ground state have?
1
What’s the formula for the movement of electrons between energy levels
hc / wavelength
What is a cool gas?
A gas containing atoms in their ground state.
