Answer to Question #302953 in Atomic and Nuclear Physics for Physicshelp

Question

If a Saturn V rocket with an Apollo spacecraft attached had a combined mass of 3.1 × 10⁵ kg and reached a speed of 11 km/s, how much kinetic energy would it then have?

Answer 1

The velocity of rocket is significantly smaller than light speed, so the kinetic energy is $E = \dfrac{mv^2}{2} = \dfrac{3.1\cdot10^5\,\mathrm{kg}\cdot(11\cdot10^3\,\mathrm{m/s})^2}{2} = 1.88\cdot10^{13}\,\mathrm{J}.$