Chapter 12 Flashcards
When does lights occur
When an electron jumps from an outer orbit to an inner oribjt and it gives off energy in the visible spectrum of electromagnetic radiation
Electromagnetic radiation is both a
Particle and wave it had characteristics of both
Does electromagnetic radiation need a medium to travel through
No they’re transverse waves
Speed of light
186,000 mi/s all waves to this speed
Lightyr
Distance light travels in a yr so 186,000m/s for a yr
One year
Earth makes one trip around sun
Describe tides
The moon pulls the ocean and the ocean budges on sides bc the moon and earth are caught in each other’s gravity therefore two high tides and two low every day
Why does light not follow Newtonian laws
Bc the speed of light is always the same speed even if the observer or source is moving
White light
No such thing it’s but all the colors coming at once and our brain puts it together as being white
What colors do human see in
Red green blue when they come together we see other colors
Light waves
Reflect and refract
Lenses
Curved pieces of glass that make image larger or smaller
Two types of lenses and describe
Convex- lens bumps out in front and maginifies image (nearsighted)
Concave - caves in shrinks image for farsighted ppl
Mirages
Occur when light bends as it goes between gaps between hot and cold air and produces shimmering image above blacktop
Rainbows
When light is being refracted from raindrops the sun must be behind you and the storm must be in front of you
Polarization
The axis of rotation of light is random it can come at any angle
3D effect
Occurs when projector is projecting on two axis of rotation and it matches with the lenses in 3D glasses
Pacemakers
Devices that are implanted under skin and have wires that go into two locations in the heart that makes it beat regularly.
Broken microwaves
Dangerous for ppl withpacemakerds with the microwaves could leak in hot the pacemaker and screw it up
3 types of Uv light and describe
UVa- harmless, used in black lights and for glow-in-the-dark things it is non-ionizing
UVb- dangerous skin cancer and sunburn ionizing
UVc - very very dangerous ionizing skin cancer used for water purification blocked by o zone
Lasers
Light amplification by stimulated emission
Who made first laser
Maiman
What do lasers do
Have coherent light which means they organize the troughs and crests this makes the light dense bc it can be compressed without waves hitting each other
Who measured speed of light
Michaelson
Time
Relative to the distance and speed of the observer and source of light
Example people near click see time before ppl farther away bc light has to clinch off clock and back to us
Time dilation
When the time gets stretched when objects approach speed of light
Equation for speed
Speed= distance/time
Lorentz contraction
When something is moving past the observer at close to the speed of light it loses dimension in the direction their traveling
Mass increase
When objects as they approach the speed of light their mass becomes the mass of the entire universe
Speed of light=mass of universe
Gravity
A distortion of the time space continuum caused by the fact that there’s lots of mass. Light is distorted by gravity
