Light Flashcards
Electromagnetism doesn’t ??
Need a medium to travel through bc electric wave pushes the magnetic wave and magnetic wave pushes the electric one
Speed of light
186,000 miles per second
When you see sun light it’s actually an imagine from
81/2 minutes ago
Closest star is
2 light years away
Explain how the moons gravity pulls the ocean
It pulls ocean on both sides of the earth causing the ocean to bulge causing 2 high tides and 2 low tides
E=mc2
Energy = mass speed of light
Energy and mass are
Proportional
White light is
All colors are (how did Newton show this)
All the colors together
Pieces of white light and he used a prism and shone white light through it
refraction
Bending of light
Lens
Piece of glass that either magnifies an object or makes it smaller
Explain mirage
Say there’s a car on the road and the sun is shining down, the hot air is rising to the cool air and the sun light bending between the warm and cool air causes a mirage
Double rainbows
What do you need to see a rainbow
Are opposites
Red-purple purple- red
Sun behind you and storm Infront of you
Polirazarion
Axis of rotation of light is random
It refeacts 1/2 the light so they all have the same axis
2 polarizes in opposition
Block out the light
Radio waves
Length
Commonly used for
Length of soccer field
Radio (am=amplitude modulation & fm=frequency modulation)
Tv
Cellphones
Microwaves
Shorter than
Used for
Shorter than radio waves
Microwaves
GPS (global positioning system)
Radar ( radio detection and ranging)
Danger or pacemakers and microwaves
Microwaves can leak and cause pacemakers to stop working and cause heart attacks
Infared
Heat
Just below Red visable light
You can’t see it
Ultraviolet light
UVA - non ionizing visible light and harmless
UVB - ionizing sunburn
UVC - ionizing X-rays, blocked by our ozone in our atmosphere
Time dialation
Time is stretched when objects approach speed of light
Say Me.Moore was in a truck then speed would equal distance divided by time but an observer who is far away speed = DISTANCE divided by TIME since the distance is bigger the time has to be bigger to and now time is stretched and the object pictures in slow-motion
Light is caused by
Electrons orbiting and giving off quanta
If Courtney travels into space/tike travel example
If Courtney travels into space at half the speed of light and is gone for two 1/2 years. She was actually only gone for two years that I was waiting still for 2 1/2 but the time was different up in space
Lorenz contraction
When I basketball is moving it looks smaller and kind of distorted and if a basketball is moving at the speed of light it would look like a stick but it never loses its shape it just appears different
How is mass different when something is moving at the speed of light
Yes it becomes infinite flight and the mass increases but an object can never quite reach a speed of light because if I did the mass would equal the mass of the universe
Gravity is proportional to
Mass
Gravity is the distortion of
The time space continuum caused by the fact that there’s so much mass
Maxwell and Einstein say light is a light wave and is now called
Electromagnetic radiation
