Questions and Answers
What is wavelength?
The separation of peaks in a wave, typically represented by the symbol λ (lambda).
What is the speed of a wave?
The speed at which its wave peaks move.
What is frequency?
The rate at which wave peaks pass a point in space, measured in Hertz (Hz).
What formula describes the relation between wavelength, speed, and frequency?
Signup and view all the answers
What are the properties of electrons, protons, and neutrons?
Signup and view all the answers
Explain electric fields.
Signup and view all the answers
What is the link between light and vibrating electric fields?
Signup and view all the answers
What is the electromagnetic spectrum?
Signup and view all the answers
Explain the transmission of light through the Earth's atmosphere.
Signup and view all the answers
Describe the structure of atoms.
Signup and view all the answers
How many protons and neutrons are in hydrogen, helium, and carbon?
Signup and view all the answers
How many protons and neutrons are in nitrogen, oxygen, iron, and uranium?
Signup and view all the answers
What is Kirchhoff's First Law?
Signup and view all the answers
What is a spectrum?
Signup and view all the answers
What does the equation E = hν represent?
Signup and view all the answers
What occurs during the emission and absorption of photons by electrons?
Signup and view all the answers
What does temperature measure?
Signup and view all the answers
What are Kirchhoff's three laws?
Signup and view all the answers
What are the properties of black body radiation?
Signup and view all the answers
What is the equation for the luminosity of an object emitting black body radiation?
Signup and view all the answers
Describe the Hertzsprung-Russell (H-R) Diagram.
Signup and view all the answers
How can you interpret the H-R diagram?
Signup and view all the answers
How is density defined?
Signup and view all the answers
How can you find the volume of a sphere?
Signup and view all the answers
Name three ways in which star temperatures can be measured.
Signup and view all the answers
How can you identify chemical elements in stars?
Signup and view all the answers
Study Notes
Wavelength
- Defined as the distance between wave peaks, symbolized by λ (lambda).
- Commonly measured in Ångstroms for light, with wavelengths corresponding to color.
Speed (of Waves)
- The velocity at which wave peaks travel.
Frequency
- Describes how often wave peaks pass a designated point, measured in Hertz (Hz) or cycles per second.
- Represented by symbols f or ν (nu).
Relationship Between Wavelength, Speed, and Frequency
- Expressed by the equation: Wavelength × Frequency = Speed (λν = c).
Properties of Fundamental Particles
- Electrons: Mass = 9 x 10⁻²⁸ grams, negative charge.
- Protons: Mass = 2 x 10⁻²⁴ grams, positive charge.
- Neutrons: Mass similar to protons (2 x 10⁻²⁴ grams), no charge.
- Protons and neutrons are approximately 2000 times heavier than electrons.
Electric Fields
- Surround electric charges, exerting forces on other charges; oppositely charged particles attract, like charges repel.
Light & Vibrating Electric Fields
- Light is a form of electromagnetic radiation created by vibrating electric fields, which induce vibrations in electrons in the retina, perceived as light.
Electromagnetic Spectrum
- Encompasses all types of light from radio waves to gamma rays; visible light ranges from 4000 Å to 7000 Å.
Transmission of Light Through Earth's Atmosphere
- Visible light generally passes through the atmosphere, while other wavelengths can be absorbed or reflected by gases like water vapor and carbon dioxide.
Structure of Atoms
- Atoms consist of a nucleus with protons and neutrons, surrounded by fast-moving electrons in defined energy levels.
Atomic Composition of Common Elements
- Hydrogen: 1 proton, 0 neutrons.
- Helium: 2 protons, 2 neutrons.
- Carbon: 6 protons, 6 neutrons.
- Nitrogen: 7 protons, 7 neutrons.
- Oxygen: 8 protons, 8 neutrons.
- Iron: 26 protons, 30 neutrons.
- Uranium: 92 protons, 146 neutrons.
Kirchhoff's Laws
- First Law: Continuous spectrum emitted by hot solids, liquids, or gases.
- Second Law: Rarefied hot gas emits light at specific wavelengths (emission line spectrum).
- Third Law: Light passing through cool gas produces absorption line spectrum.
Spectrum
- Graph plotting light intensity versus wavelength, typically measured in Ångstroms.
Einstein's Equation (E = hν)
- Established light's quantized nature, leading to quantum mechanics; h is Planck's constant (6.6 x 10⁻²⁷).
Photon Emission & Absorption
- Transition of an electron between energy levels involves emission or absorption of a photon, with frequency and wavelength determined by energy differences.
Temperature & Kelvin Scale
- Temperature reflects atomic and molecular movement rates; Kelvin = Celsius + 273.
Black Body Radiation
- Hot objects emit more energy; emission spectrum has a broad maximum influenced by temperature. Key equations include:
- Luminosity (L) = Area × T⁴
- Peak wavelength (λmax) = 2.9 × 10⁷/T.
Hertzsprung-Russell (H-R) Diagram
- Plots stars based on temperature (backwards axis) and luminosity (vertical axis in Solar Luminosities); clusters indicate different star types.
Star Temperature Measurement
- Determined via spectral type, color, or wavelength of peak emission.
Chemical Element Identification in Stars
- Unique patterns of emission/absorption lines allow element identification; each element has characteristic wavelengths due to differing atomic energy levels.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Description
Study essential concepts of waves with these flashcards covering definitions and key terms like wavelength and wave speed. Perfect for reinforcing your understanding of physical phenomena related to light and sound. Ideal for students preparing for exams in physics.