Chapter 5: Light and Matter Flashcards
What is emmission?
When light is produced by matter.
What is absorption?
When light is absorbed by matter (along with its energy).
What is transmission?
Occurs when light passes through matter.
What is reflection/scattering?
Occurs when light bounces off of matter.
What is the frequency of light?
The cycles of light per second.
What is an element’s atomic number?
The number of protons in its nucleus.
What is an element’s atomic mass number?
The number of protons and neutron in its nucleus.
What is an isotope?
Versions of an element with different numbers of neutrons are called isotopes of that element.
What is a charged atom called?
An ion.
What is the process of stripping electrons from an atom called?
Ionization
What is plasma?
A gas consisting of ions and electrons.
What is spectoscopy?
The process of obtaining a spectrum an reading the information it contains.
What does intensity of light refer to?
It refers to the amount of light present.
What is a continous spectrum?
A spectrum that spans a range of wavelengths without interuption.
What is an emmision line spectrum?
A thin or low density cloud of gas that emits light only at specific wavelengths depending on its composition and temperature. This results in bright emmision lines on a black background.
What is an absorption line spectrum?
A cloud of gas inbetween the observer and a light source will absorb specific wavelengths of light. This results in a continuous spectrum of light with dark absorbtion lines. This only works if the cloud is cooler than the light source.
What are the two laws of thermal radiation?
The Stefan-Boltzman Law and Wien’s Law.
What is The Stefan-Boltzman Law?
Each square meter of a hotter object’s surface emits more light at all wavelengths.
What is Wien’s Law?
Hotter objects emit photons with higher average energy.
What does a blue shift signify?
An object is approaching us.
What does a red shift signify?
An object is moving away from us?
What type of motion can a doppler shift identify?
The radial component of motion.
What type of motion can a doppler shift not identify?
The tangential component of motion.
