Particles 2 Flashcards
What force is used in decay interactions?
The Weak Nuclear Force
Specifically how are strange particles made?
They are made in pairs
What was the pion neutral particle used in the past to represent?
The strong nuclear force
What are the base units for joules?
J=kgm*2s*-2
What is the formula for kinetic energy
Kinetic energy = 0.5mv*2
What is the equation for de Broglie’s wavelength?
Wavelength=h divided by momentum
What is an absorption spectrum?
a spectrum with a coloured background and black lines showing the missing frequencies in the spectrum.
What is an emission spectrum?
It is a spectrum with a black background, with coloured lines representing the emitted frequencies.
What is a photon?
a quanta of light energy - can be a particle or a wave
What is another name for the energy level n= infinity?
the convergence limit/ionisation limit
What happens when an electron absorbs a photon?
the electron at the ground state of the atom if excited and moves up to higher energy levels. Electrons can also then de-excite and cause photon of some energy to be emitted. The electron will then move down to lower energy levels.
What is important about the amount of energy absorbed by an electron?
To move up energy levels, the electrons need to absorb a discrete amount of energy greater than the next energy level.
Why are there black lines on the spectrum of light from the Sun?
As as the Sun’s radiation passes through the cooler gases in the outer layers of the Sun, some frequencies of the spectrum are absorbed by atoms in the cooler gases.
How does a flourescent tube work? step 1 and 2
How does a flourescent tube work? step 3 and 4
How does diffraction work?
