What was Einstein known for?
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What was Einstein known What was Einstein known for? for? Tobacco lobbyist? Fashion? His hair? Stamps? His Music? His TONGUE? OR.. …
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Tobacco lobbyist?. Stamps?. His hair?. His Music?. Fashion?. His TONGUE?. What was Einstein known for?. OR..…. Einstein is probably best known as the father of…. Special Relativity. “I sometimes ask myself how it came about that I was the one to develop the theory of relativity. - PowerPoint PPT Presentation
Transcript of What was Einstein known for?
What was Einstein known What was Einstein known for?for?
Tobacco lobbyist?
Fashion?
His hair?
Stamps?
His Music?
His TONGUE?OR..…
Special RelativitySpecial Relativity
Einstein is probably best known as the father of….
The reason, I think, is that a normal
child never stops to think about problems of space and time. But my intellectual development was slowed, as a result of which I began to wonder about space and time only when I had already grown up.”
? ? ? ?
“I sometimes ask myself how it came about that I was the one to develop the theory of
relativity.
BackgroundBackground
Michelson-Morley Experiment
Ether
Annus Mirabilis
Maxwell- EM Radiation
Annus MirabilisAnnus MirabilisThe miracle yearThe miracle yearThe miracle yearThe miracle year
Early 1905 Photoelectric Effect
June 1905 Theory of Special Relativity
Late 1905 Brownian Motion
What is What is Relativity?Relativity?
Or maybe it is easier to ask….
What is absolute?
All things are Relative
Time? Mass?Length?
Are you moving right now?
Needs some point of comparison
Try this outTry this outConnect ALL nine dots using only four straight
lines without taking your pen off the paper
What pre-conceived ideas (absolutes) are you holding on to?
Gedanken Gedanken “Mind experiment”
Consider a device which will measure the time it takes light to bounce back and forth off of two mirrors
If the mirrors are 4 m apart, what would be the total distance traveled by one reflection? 8 m
GedankenGedanken part deuxpart deux
Now lets consider the same situation on a moving vehicle and someone observes the mirrors from off the moving vehicle.
If the vehicle moves 3 m in the same time for light to reach the top how far does light seem to travel in one reflection?
10 m
Famous QuotesFamous Quotes“Nature allows no paradoxes. If you
think you have encountered one; check your premises”- Ayn Rand
??? 10 m = 8 m ???
Einstein’s Relativity
Postulate
Definition
• 1. To make claim for; demand.
• 2. To assume or assert the truth, reality, or necessity of, especially as a basis of an argument.
• 3. To assume as a premise or axiom; take for granted.
The Tabletop Explainer
First PostulateFirst Postulate1. Physical laws are the same in all
frames of reference.
That is; any event within a portion of space (a frame) can be specified by three spatial dimensions (x, y, z, t). Also, the laws that apply to us in everyday circumstances (Newton's laws) also apply within each frame of reference
2. The speed of light is constant.
Second PostulateSecond Postulate
By this it is meant that in a vacuum, such as in space, the speed of light is alwaysalways the same, regardless of the speed of someone observing it.
c = 3.0 x 10 8 m/s
Speed LimitsSpeed LimitsThe maximum speed in our universe is the speed of light.
Nothing in our universe can travel at the speed of light except other forms of electromagnetic radiation
c = 3.0 x 10 8 m/sc
Newtonian vs. Newtonian vs. Relativistic Relativistic MechanicsMechanics
Newtonian Mechanics
Relativistic Mechanics
What is for the following speeds?
Gamma Gamma FactorFactor
Speed (m/s)
25
343
2000
0.1c
0.4c
0.5c
0.6c
0.7c
0.8c
0.9c
0.99c
Gamma ()1.00
1.00
1.00
1.01
1.09
1.15
1.25
1.40
1.67
2.29
7.09
Time DilationTime Dilation
Where
to is the time in the rest frame
t is the time in the frame in relative motion
What happens as one travels closer to the speed of light?
Length Length ContractionContraction
What happens as one travels closer to the speed of light?
Where
lo denotes the rest frame length
Where
mo denotes the rest mass
Relativistic MassRelativistic Mass
This is the quickest way to show that an object cannot travel at the speed of light…
What happens as one travels closer to the speed of light?
They would require infinite energy to accelerate
A two stage rocket is moving with speed 0.6c when it separates. The second stage moves away from the first rocket with a speed of 0.6c. What is the speed of the second rocket with respect to the earth?
Addition of Addition of VelocitiesVelocities
0.88 c
What are the units of Energy?What are the units of mass?What are the units of c?
Mass-Energy Mass-Energy EquivalenceEquivalence
The End?
