Year 12 Physics - Special Relativity

What does special relativity apply to

inertial (non accelerating) reference frames

What are Einstein’s two postulates

The speed of light in a vacuum is an absolute constant

all inertial frame of reference are equivalent

what does it mean for inertial reference frames to be equivalent

that the laws of physics apply to them

what are rest measurements

those made by observers within the same reference frame as the moving object (hence unaware of the movement)

what denotes rest measurements

the subscript 0

why can nothing reach the speed of light

as it would require infinite energy

describe the measurement v

the velocity of a body as seen by a stationary observer

describe the measurement u’

the velocity of an object as seen by someone in the same frame of reference as the body

describe the measurement u

the velocity of an object as seen by a stationary observer

State and explain Galileo’s suggestion

he suggested that the natural state of objects is in uniform motion

this meaning that an object will continue in its’ state of motion without a force, supported by the principle of inertia

How did velocities work in newtonian physics

Newton followed the principle that velocities of objects and different reference frames could simply be added

What did Einstein believe about velocity

that there is no absolute velocity

it can always be stated as relative to some other object

what did scientists believe the aether was

a masless, rigid medium which carried electric and magnetic fields