Since the angle of reflection is the same as the angle of incidence, two congruent triangles can be formed when u draw the diagram properly (yours isn't correct). Then, for him to see the top of his head, a ray of light from the tip of his head has to reach his eyes. Therefore, another two...
Question 1:
Current particle accelerators are only able to speed up particles up to around 0.16c. However, in nuclear reactors, radioactive nuclei release subatomic particles, i.e. electrons, at more than 0.75c. To increase efficiency and perhaps to observe how particles collide at high speeds...