As a radioactive fuel rod from a nuclear reactor is immersed in deep water, an intense blue glow is produced; this is the Cerenkov effect, in which particles emit light when traveling in a material, at speed: v >c/n , where n is the index of refraction of the material. But it is impossible to exceed the speed of light. a) What does c/n represent in this equation? b) How is the Cerenkov effect possible? c) What particle is most likely to be responsible for this?