Astronomy Essential Cosmic perpective quiz chapter 5 Flashcards
What does light from the sun do?
warms the earth, drives the wind and rain, and powers photosynthesis in plants and so the food the chain
What can light from distant objects tell us?
their composition temperature, speed and other things
how do we experience light?
by asorbing it in our eyes to see and in our skin as heat , radient energy A kind of KE
What do humans use up to as?
100-w light bulb
What was galileo able to measure?
the speed of sound but was unable to measure the speed if light, because the speed of light was about million times faster
what was Roemer successful at? and what was he able to realize?
measuring the speed of light. and he was able to realize the reason for the 16 minute transit delays when jupiter was at conjuction was because it took 16 minutes for the light to traverse the earths orbit
What did maxwell derive?
4 equations relating electricity and magnetism that theroretically joined them.. His theory predicted the spped of EM waves produced by accelerating charges. The speed came out as the speed of light
what was maxwells theory arent? prediction?
Maxwell predicted em waves of frequencies beyond visible light confirmed when hertz found radio waves and roentgun discovered x rays
True statment
The visible part of of the spectrum /rainbow from lowest to ighest requency: red, orang, yellow, blue, green, violet
what is the EM spectrum from lowest to highest?
Radio, microwave IR visible UV xrays Gamma rays
Less radiation and frequencies arent
typically harmful to us , but those of higher frequencies are
What are the four properties of waves
wavelength (distance from peak to peak) frequency (how frequently they pass by amplitude (how strong) and speed (how fast through the median
what is light , sound and water?
light is transverse wace the variation is transverse to the wave direction . sound is a longitude wave (the variation is froward and back water waves are surface waves, transverse and longitudinal combined (a kind of circlar motion
because light is tranverse what does it produce?
polarization
what is the equation for waves?
transverse or longitude v=Kf
true statement
as A goes up then f goes down. long A means low frequency. To change v requires that you change the medium
what are the different frequencies we perceive?
sound/light as differing pitch/color. We perceive differing amplitudes of sound /light as differing loudness/brightness
what are sound, water and wire waves known as?
Mechanical waves since their waving is due to disturbing the medium. Em waves arent mechanical waves, but they are transverse since the electric field varies in a direction perpendicular to the velocity direction
what is the four wave phenonmena light exibits?
reflection, refraction, diffraction, and interference , so light is a wave
what is reflection, reffraction, diffraction, and interference?
reflection is the bending of waves (such as through glass of water) diffraction is the spreading out of wavess (such as at small openings) and interference is the adding of waves at the same point ( such as water waves from dropped stones in a pond)
what is constructive interference and destructive?
is where the peaks of two waves add to make a more pronounced wave. Destructive interference is where the peak meets through and the waves cancel
what does adding more sound do to wave? what does reducing noise to a machine operator do?
adding more sound can make things quieter. You can reduce the noise a machine operator hears by adding the same engine noise inverted.
what did newton explain?
light by treating it as a particle, but thomas young, showed that light is a wave because it produced the multiple peaked 2 slit interference pattern
what does light exihibit?
Light exhibits other phenomena implying that its a particle called a photon. Since light also exhibits the phenomena of waves, light is a wave particle thing A “wavicle”