Home
Subjects
Create
Search
Log in
Sign up
Upgrade to remove ads
Only $2.99/month
Science
Physics
Relativity
Physics chapter 35
STUDY
Flashcards
Learn
Write
Spell
Test
PLAY
Match
Gravity
Terms in this set (76)
the place from which motion is observed and measured is called
frame of reference
Einstein rejected the classical idea that space and time are
independent of each other
what is special about the ratio "distance traveled per unit of time"
it is constant for light
a postulate of special relativity is that the speed of light
for all observers is a constant
compared to clocks in a stationary reference frame, clocks in a moving reference frame run
slower
clocks on a spaceship moving at high speed relative to the earth run more slowly when viewed from
earth
you look at the clock on the big ben tower in london and it reads 12 noon. if you could hypothetically travel away from the clock at the speed of light and view it with a telescope it would
be frozen at 12 noon
we are actually looking into the past when we look at
-our physics book
-a distant star
according to relativity theory, if a space trip finds a son or daughter biologically older than their parents, then the space trip is taken by the
a. parents
b. son or daughter
parents
a light source blinks once per second in its own frame of reference. As you approach the blinking source, you observe the frequency of blinks to be
more than 1 hz
As a light source blinking at a steady rate approaches you at an increasing speed (accelerating towards you) the rate at which the blinks encounter you
increases
as you recede from a steady light source, the wavelength of the emitted light appears
longer
according to special relativity, tomorrow's travelers can travel
only forward in time
to outside observers at rest, the overall sizes of objects traveling at relativistic speeds are
smaller
an astronaut traveling forward at .87c holds a meterstick in spear-like fashion. This astronaut sees the spears length as
1m
an astronaut traveling forward at .87c holds a meterstick in spear-like fashion. An observer at rest sees the spear's length as
.5m
Radioactive muons formed high in the atmosphere have an average lifetime of 2 millionths of a second and travel toward Earth at nearly the speed of light. Because of their altitude most of them should have decayed by the time they reach the Earth's surface, according to pre-relativity physics. They don't because they
-travel a shorter distance due to length contraction
-live longer due to time dilation
according to e=mc2
mass and energy are related
Electrons fired in vintage TV tubes traveled at about 0.25 times the speed of light, having more momentum and energy than would be required classically to get that speed. Strictly speaking, this
increased your electric bill
a vantage point with respect to which position and motion may be described
frame of reference
1. all laws of nature are the same in all uniformly moving frames of reference
2. the speed of light in free space has the same measured value regardless of the motion of the source or the motion of the observer; the speed of light is a constant
postulates of the special relativity theory
occurence at the same time. two events that are simultaneous in one frame of reference need not be simultaneous in a frame that is moving relative to the first frame
simultaneity
the 4 dimensional continuum in which all events take place and all things exist. Three dimensions are the coordinates of space, and the 4th is time
spacetime
the slowing down of time for a moving object as measured by those who see it as moving
time dilation
the contraction of space in an observer's direction of motion as a result of speed
length contraction
a mysterious something.. thought to fill space and to serve as a frame of reference attached to space itself.
ether
splits a light beam into two parts and then recombines them to form an interference pattern after they have traveled along different paths
michelson-morley interferometer
designed to measure the motion of earth through space
michelson-morley
advanced the idea that the speed of light in free space is the same in all reference frames
Einstein (this idea was contrary to the classical ideas of space and time)
time and space are not independent
special theory of relativity
who saw no need for ether? Why
Einstein because all motion is relative
all laws of nature are the same in all uniformly moving frames of reference
first postulate
if you were on a train with no windows, would you be able to determine if you were moving?
no
can experiments reveal absolute motion?
no
the speed of light in free space has the same measured value for all observers, regardless of the motion of the source or the motion of the observer. The speed of light is a constant
second postulate
the speed of light is measured to be the same regardless of the speed of the source or the receiver
second postulate
a light source placed in the middle of a rocket will reach all ends of the rocket at the same speed
simultaneity
* for an observer not in the same reference frame, those two events are not simultaneous. as light travels out from the source, this observer sees the ship move forward, so the back compartment moves towards the beam while the front moves away from it . Therefore, the beam going to the back of the compartment has a shorter distance to travel than the beam going forward
...
two events that are simultaneous in one frame of reference need not be simultaneous in a frame moving relative to the first frame
simultaneity
when we look at the stars we are actually looking backward in time
...
what specifies the position of a point in space?
distances along the x axis, y axis, and z axis
Do two side by side observers at rest that agree on measurements of space and time intervals share the same realm of spacetime?
yes
stretching out of time
time dilation
when do clocks move more slowly?
when accelerating
is time dilation an illusion?
no
if a clock flies by us at the speed of light, how would it appear?
frozen
truly ageless
photons
how is time dilation confirmed in a lab setting?
with particle accelerators
for human beings, time has only one direction. Which direction is that?
forward
objects appear shorter when they move by us at relativistic speeds
length contraction
***** contraction only takes place in the direction of motion
...
***if an object is moving horizontally, no contraction takes place vertically
...
***if an object is moving horizontally, no contraction takes place vertically
...
where does contraction take place?
in the direction of motion
observers in a moving frame will see our meter sticks contracted, while we see theirs contracted. The effects of relativity are always attributed to the other person.
...
when does an object require more momentum?
when you apply more impulse to an object that is free to move
if you double the impulse, what does that do to the momentum?
doubles it
p=ymv
relativistic momentum is greater than mv by a factor of y
why is it impossible for an object to reach the speed of light?
the object would require infinite impulse
as speed approaches c, what happens to y?
it approaches infinity
a piece of matter, even at rest and not interacting with anything else, has an energy of being. This is called
rest energy
what did Einstein conclude about mass and energy?
that it takes energy to make mass and that energy is released if mass disappears.
e=mc squared
the amount of energy is related to the amount of mass
to the general public, Einsteins famous equation is synonymous with
nuclear energy
how many tons of mass are converted to radiant energy in the sun in 1 second?
4.5 million tons
the contributing factors to the amount of change in mass
the amount of energy released and the amount of mass involved
for all chemical reactions that give off energy, there is a corresponding decrease in mass of about
1 part in a billion
and for nuclear reactions?
1 part in a thousand
a change of the energy of any object at rest is accompanied by a change in its
mass
when does a filament in a lightbulb have more mass?
when it is turned on
***a wound up clock has more mass when its wound up than unwound
...
mass is
congealed energy
a small amount of mass stores a ______amount of energy
large
Einstein's equation states that
mass and energy are the same thing. mass is congealed energy
any new theory or any new description of nature must agree with the old where the old gives correct results
correspondence principle
****for everyday speeds, the momentum, length, and time of moving objects are essentially unchanged
...
THIS SET IS OFTEN IN FOLDERS WITH...
Ch 26 Physics
21 terms
Chapter 35
14 terms
ch 35 hw
51 terms
ch 35! use this one
58 terms
YOU MIGHT ALSO LIKE...
Physics Test 4
69 terms
Physics: Space-Time CH 15 (packet)
24 terms
Chapter 15&16 test-physics
40 terms
SQ 10
13 terms
OTHER SETS BY THIS CREATOR
tract functions
9 terms
Shoulder Rehabilitation
40 terms
Pedretti chapter 39
19 terms
Fine Motor
3 terms
OTHER QUIZLET SETS
Industrial Revolution
15 terms
Healthcare Ethics - Chapter 8
25 terms
anther final review
68 terms
UNE Pharmacology (Summer)
137 terms