If a robotic probe sent to Mars is designed to return a rock sample to Earth, how fast must the probe be launched from the surface of Mars in order to escape the gravity of Mars? For reference, Mars has a mass of 6 *10²³ kg and a radius of 3,400 km. A) 100 m/s B) 4,900 m/s C) 20 m/s D) 20,000 m/s E) You must know the mass of the satellite to determine the answer.

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Quizplus · Accepted Answer

The escape velocity from a planet is determined by the formula $ v = \sqrt{\frac{2GM}{R}} $, where $ G $ is the gravitational constant, $ M $ is the mass of the planet, and $ R $ is the radius of the planet. For Mars, this calculation gives approximately 4,900 m/s. The mass of the satellite is not needed to determine escape velocity.

If a Robotic Probe Sent to Mars Is Designed to Return