<Dd> E k = m γ c 2 − m c 2 = m c 2 1 − v 2 / c 2 − m c 2 (\ displaystyle E_ (\ text (k)) = m \ gamma c ^ (2) - mc ^ (2) = (\ frac (mc ^ (2)) (\ sqrt (1 - v ^ (2) / c ^ (2)))) - mc ^ (2)) </Dd> <P> This formula shows that the work expended accelerating an object from rest approaches infinity as the velocity approaches the speed of light . Thus it is impossible to accelerate an object across this boundary . </P> <P> The mathematical by - product of this calculation is the mass - energy equivalence formula--the body at rest must have energy content </P> <Dl> <Dd> E rest = E 0 = m c 2 (\ displaystyle E_ (\ text (rest)) = E_ (0) = mc ^ (2) \!) </Dd> </Dl>

What kind of energy is possessed by the following