The formula for adding velocities in "Relativities"
v' is the velocity of the man in the train frame of reference
v is the velocity of the train in the ground frame of reference
r
v is the velocity of the man in the ground frame of reference
c is the speed of light
then
v' + v
r
v = --------------
1 + v' v / c^2
r
v' is the velocity of the man in the train frame of reference
v is the velocity of the train in the ground frame of reference
r
v is the velocity of the man in the ground frame of reference
c is the speed of light
then
v' + v
r
v = --------------
1 + v' v / c^2
r