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41 Cards in this Set
- Front
- Back
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What is Inverse Square Relation?
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If the distance between earth and the moon were doubled, the gravitational force between them would decrease by 2^2 which equals four. If the distance were tripled it would decrease by 3^2 which equals nine.
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What is the equation for Newton's Law Of Gravity?
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F=-G(Mm/r^2)
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How many laws of motion did Newton develop?
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Three
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What is Newton's first law of motion?
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A body continues at rest or in uniform motion in a straight line unless acted upon by a force.
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What is Newton's second law of motion?
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The amount of change in a body's motion is proportional to the force acting on it, and along the same direction as the force.
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What is Newton's third law of motion?
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When one body exerts a force on a second body, the second body exerts an equal and opposite force back on the first body.
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What is Newton's law of gravity?
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Everything with MASS pulls on everything else with mass. Gravity is always attractive. The closer the object, the stronger the pull.
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What is the electromagnetic spectrum?
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The entire possible range of wavelengths or frequencies light can have.
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What are particles of light called?
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Photons. Each photon has a wavelength and a frequency. The energy of a photon depends on its frequencies.
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What is light frequency?
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Frequency is the number of times per second that a wave vibrates up and down.
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What is light wavelength?
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Wavelength is the distance between two wave peaks.
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What is wave speed?
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Wavelength x Frequency
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What are Gamma Rays?
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Gamma rays are very high in frequency. They also have very high energy. Damaging to humans. The atmosphere blocks Gamma rays. Can only be studied from space.
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What are X-Rays?
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Pretty high energy. Not as bad as gamma rays, too much is still bad. Medical uses. Can still only be studied from space. Gas in galaxy clusters, supernova remnants, or the suns corona.
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What is Ultraviolet (UV) light?
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Closer to visible light. Too much is a bad thing. Visible in supernova remnants and coming from very hot stars.
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What is visible light?
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Light our eyes can see. Wavelengths about as long as bacteria. About 400-700 nanometers. Produced in stars.
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What is infrared light?
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We glow in IR light. Beyond the range of human sight. Night-vision goggles. Given off by planets, some gases, and moons.
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What are radio wavelengths?
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Very wide range of wavelengths/frequencies. Used for TV, Radio, RADAR Mictrowaves.
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What is focal length on a telescope?
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The distance between the lens or mirror to the image formed of a distance light source, such as a star.
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What is a refracting telescope?
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A telescope that focuses light using a lens.
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What is a reflecting telescope?
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A telescope that focuses light using a mirror. The main mirror is called the primary mirror.
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What does the eyepiece on a telescope do?
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It magnifies the image making it easier to view.
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What is chromatic aberration?
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Color seperation that happens when you look through the refracting telescope. The lends bends shorter wavelengths more than longer wavelengths. Blue light comes to a focus closer to the lens than red light.
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What is refraction?
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Refraction is the bending of light. Our eyes uses refraction to focus light.
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What does a telescopes diameter tell us?
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The telescopes diameter tells us its light-collecting area.
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What does magnification depend on?
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Both the objective lens and the eyepiece lens.
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What does a larger objective lens provide?
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A brighter image.
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What happens when an atom reaches a point of excitation?
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Electron absorbs a photon and jumps up an energy level.
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What is ionization?
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Electron absorbs a photon and leaves. Only works if electron is in higher energy levels.
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What happens when an atom reaches a point of de-excitation?
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Electron emits a photon of energy.
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What are the three basic types of spectra?
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Continues Spectrum - All wavelengths, no breaks. Rainbows.
Emission Line Spectrum - Bright individual lines. Also called a bright-line spectrum. Electrons are moving to lower energy levels, emitting photons of light. Absorption Spectrum |
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What is Wien's law?
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Describes relationship between temperature and peak wavelengths.
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What is the Balmer Thermometer?
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Temperature from spectral lines. Can't use just it, need other elements. Strength in various lines predicts temp. Temp. predicts strength of lines.
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What is the Doppler Effect?
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When something which is giving off light moves towards or away from you, the wavelength of the emitted light is changed or shifted. The closer the object gets, the smaller the wavelength gets. The further the object goes away, the wider the wavelength gets.
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What are the seven spectral classes used, and what do they mean?
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O, B, A, F, G, K, M. O classification is the hottest star, and it goes down the line to M being the coolest. There are also sub catagories for each one, so a star could be an A3, or a G6, and so on.
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What is the sun's photosphere?
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The visible surface of the sun. It appears to be solid, but in reality it is comprised entirely of gas.
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What is are granules on the sun's surface?
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Granules only last for 10 to 20 minutes, but are constantly forming on the sun surface. They are dark spots on the sun that are considerably hotter in the center then the rest of the surface. Doppler shifts reveal that the centers are rising while the edges are sinking. Granulation is caused by convection beneath the photosphere.
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What is convection?
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Convection occurs when hot fluid rises and cool fluid sinks.
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What are supergranules?
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Super granules are regions a little over twice earths diameter that are made up of about 300 granules each. They are produced by larger currents of hot gas beneath the photosphere.
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What is the Chromosphere?
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The chromosphere lies right above the photosphere. It is only visible during a solar eclipse, and even then is perceived
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What is the sun's corona?
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The corona is too dim to be seen normally in the daytime sky. It is the outermost part of the sun's atmosphere, and is only visible to the naked eye during a solar eclipse.
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