Amber Reed Quiz

Quiz

What is light?
Light is also known as electromagnetic radiation. Visible light that splits into rainbow of color is only a tiny part of the complete spectrum of light.

What is matter?
Matter is generally considered to be a substance, usually a particle that has rest mass and most often also volume. 

How do light and matter interact?
Matter can emit,absorb,transmit or reflect light. Emission can be defined as when  a light bulb emits visible light; the energy of the light comes from electrical potential energy supplied to the bulb (fusion). Then absorption is when you place your hand near an incandescent light bulb, your hand absorbs some of the light and this absorbed energy warms your hand (heat up matter). Also, transmission:some forms of matter, such as glass or air transmit light which means allowing it to pass through ( general term for movement of E.M. through a medium). Reflection/scattering is when light can bounce off matter,leading to  what we call reflection(when bouncing is all in the same general direction) or scattering (when the bouncing is more random).

What are the three basic types of spectra?
There are basic types of spectra, one is continuous. Second is an emission line; a thin or low density cloud of gas emits light at specific wave lengths that depend on its composition and temp, producing a spectrum with bright emission lines
Thirdly is an absorption line;a cloud of gas between us an a light bulb can absorb light of specific wave lengths leaving dark absorption lines in the spectrum.

How does light tell us what things are made of?
Energy levels are possible energies of an atom, which consist of electrons in atoms can have only particular amounts of energy and now other energies in between .  Also, chemical fingerprints that make each type of atom has unique set f energy levels. Then each transition corresponds to a unique photon energy, frequency and wavelength.  Some with downward transitions produce a unique pattern of emission lines, this is because those atoms can absorb photons with those same energies,upward transitions produce a pattern of absorption lines at the same wave lengths. Each atom had a unique spectral fingerprint, and by observing the fingerprints n a spectrum tells us which kinds of atoms are present. 

How does light tell us the temperatures of planets and stars?
Thermal radiation is used to tell temperatures of planets and stars. Nearly all large or small objects emit thermal radiation,including stars, planets. Properties of thermal radiation are hotter objects emit more light at al frequencies per unit area and hotter objects emit photons with higher average energy.

How does light tell us the speed of a distant object?
Using the Doppler effect , it can tell us how fast an object is moving toward or away form us. Spectral lines are shifted to shorter wave lengths (blueshift) for objects moving toward us and to longer wavelengths (a redshift) for objects moving away from us.

How do telescopes help us learn about the universe?
Telescopes allows us to see fainter objects and to see more detail we can see with out eyes. Telescopes specialized to observe different wavelengths of light allow us to learn far more than we could form visible light alone. Light collecting area describes how much light telescope can collect,an angular resolution determines the amount of detail in the telescopic images 

Why do we put telescopes in space?
Telescopes in space are above earth atmosphere and not subject to problems caused by light pollution,atmospheric distortion of light or the fact that most forms of light do not penetrate through the atmosphere to the ground.

How is technology revolutionizing astronomy?
Technology makes it possible to build more powerful telescopes ad to enhance the capabilities of existing telescopes. Two key technologies are adaptive optics, which can overcome the distorting effects of earth's atmosphere, and interferometry, in which individual telescopes are linked in a way that allows the to obtain the angular resolution of much larger telescope

Amber Reed