Ngu Physics Special Relativity

Front 1

proper time

Back 1

time measured by a single clock between events that occur at the same place as the clock.

Front 2

proper length

Back 2

the length measured by someone who is at rest with respect to the distance being measured.

Front 3

rest mass

Back 3

invariant quantity which is the same for all observers at various reference points

Front 4

Young's modulus

Back 4

a measure of the stiffness of an isotropic elastic material. stress/strain

Front 5

stress

Back 5

a measure of internal forces acting within a deformable body

Front 6

strain

Back 6

the transformation of a body from a reference configuration to a current configuration

Front 7

force constant

Back 7

the ratio of the force to the deformation of a system whose deformation is proportional to the applied force.

Front 8

Bradley

Back 8

built apparatus to determine the position of stars change with time of year; the earth does not drag the ether.

Front 9

Einstein

Back 9

theory of relativity

Front 10

Fitzgerald

Back 10

2nd ether experiment following Michelson/Morley

Front 11

Lorentz

Back 11

It reflects the surprising fact that observers moving at different velocities may measure different distances, elapsed times, and even different orderings of events.

Front 12

Michelson

Back 12

experiment to determine how far ether is carried by earth

Front 13

Ritz

Back 13

the speed of light might depend on the velocity of the source

Front 14

de Sitter

Back 14

proved Ritz wrong

Front 15

Brecher

Back 15

observation of double stars using x-rays; extinction length for x-rays is ~300 light years

Front 16

Hooke's Law

Back 16

an approximation that states that the extension of a spring is in direct proportion with the load applied to it; says that strain is directly proportional to stress

Front 17

The postulates of special relativity

Back 17

The principle of relativity - the laws by which the states of physical systems undergo change are not affected, whether these changes of state be referred to the one or the other of two systems in uniform translatory motion relative to each other.

The principle of invariant light speed - light in a vacuum propagates with the speed c in at least one system of inertial coordinates regardless of the state of motion of the light source

Front 18

Michelson-Morley experiment

Back 18

designed to detect motion of the earth through the ether. Discovered there was no ether.

Front 19

Bradley's observations of the aberration of starlight

Back 19

is an astronomical phenomenon which produces an apparent motion of celestial objects about their real locations

Front 20

de Sitter's double star observations

Back 20

found no cases where the stars' images appeared scrambled; supported relativity theory; Ritz proposed variable speed of light.

Front 21

Brecher's double star observations with x-rays

Back 21

extinction length for x-rays is ~300 light years; in theory, x-rays are more energetic than ordinary light

Front 22

simultaneity

Back 22

the concept that simultaneity-whether two events occure at the same time - is not absolute, but depends on the observer's reference frame

Front 23

Lorentz transormations

Back 23

describes how, according to the theory of special relativity, two observers' varying measurements of space and time can be converted into each other's frames of reference