Q: How do velocities add? If I’m riding a beam of light and I throw a ball, why doesn’t the ball go faster than light?
Imagine pitching great Walter Johnson throws a baseball at 0.3c (30% of light speed, or about 200 million mph). In Walter’s frame (top) the light is (naturally) traveling at light speed, and the ball is traveling slower than that. You’re always restricted by the fact that, from your own point of view, you’re sitting still and light is traveling at light speed (try it!). For example, when you say “half of light speed” what you’re saying is “ “. At low (compared to light) speeds vw is overwhelmed by c2 and is very close to 1.