An unstable particle is at rest and suddenly breaks up into two fragments. No external forces act on the particle or its fragments. One of the fragments has a velocity of +0.850c and a mass of 1.68 x 10'27 kg, and the other has a mass of 5.91 x 10'27 kg. What is the velocity of the more massive fragment {as a multiple of c)? (Hint: This problem is similar to Example 6 in Chapter 7.} Unstable particle at rest ":2 \"'1 "2 l'1 4 > Recalling fragments Number n Units V