Planet Zero has a mass of 5.0 *1023 kg and a radius of 2.0 * 106 m. A space probe is launched vertically from the surface of Zero with an initial speed of 4.0 km/s. What is the speed of the probe when it is 3.0 *06 m from Zero's centre?
A)3.0 km/s
B)2.2 km/s
C)1.6 km/s
D)3.7 km/s
E)5.9 km/s

Question

Quizplus · Accepted Answer

The speed of the probe can be found using the conservation of energy principle. The initial kinetic energy plus the initial gravitational potential energy equals the final kinetic energy plus the final gravitational potential energy. Solving this equation gives the final speed as 2.2 km/s.

Planet Zero Has a Mass of 5