IB HL Physics 2025-32 - A5. Galilean and special relativity

A5. Galilean and special relativity

How do observers in different reference frames describe events in terms of space and time?

How does special relativity change our understanding of motion compared to Galilean relativity?

How are space–time diagrams used to represent relativistic motion?

How are equations of linear motion adapted in relativistic contexts?
Why is the equation for the Doppler effect for light so different from that for sound?
Special relativity places a limit on the speed of light. What other limits exist in physics? (NOS)

reference frames
that Newton's laws of motion are the same in all inertial reference frames and this is known as Galilean relativity
that in Galilean relativity the position x′ and time t′ of an event are given by x′ = x–vt and t′ = t
that Galilean transformation equations lead to the velocity addition equation as given by u′ = u–v
the two postulates of special relativity
that the postulates of special relativity lead to the Lorentz transformation equations for the coordinates of an event in two inertial reference frames
that Lorentz transformation equations lead to the relativistic velocity addition equation
that the space–time interval Δs between two events is an invariant quantity
proper time interval and proper length
time dilation as given by Δt = γΔt0
length contraction
the relativity of simultaneity
space–time diagrams
that the angle between the world line of a moving particle and the time axis on a space–time diagram is related to the particle’s speed as given by tan θ =v/c
that muon decay experiments provide experimental evidence for time dilation and length contraction.