Question

A particle moves at a speed such that its kinetic energy just equals its mass energy. what is the speed of the particle?

a. 3 x 108 m/s;

b. 2.6 x 108 m/s;

c. 2.82 x 108 m/s;

d. 2.3 x 108 m/s

Answer 1

I believe it is B. I could be wrong though.