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The planet Mars has two moons, if one of them has a period 7 hours, 30 minutes and an orbital radius of 9.0 × 10^3 km. Find the mass of Mars. Given 4π^2/G = 6 × 10^11 N^-1 m^-2 kg^2

1. 5.96 × 10^19 kg
2. 3.25 × 10^21 kg
3. 7.20 × 10^25 kg
4. 6.00 × 10^23 kg

Correct answer: 6.00 × 10^23 kg

Solution

The correct option is right because it accurately reflects the mass of Mars, calculated using Kepler's third law of planetary motion, which relates the orbital period and radius of a moon to the mass of the planet it orbits. The provided values and constants lead to the conclusion that Mars has a mass of approximately 6.00 × 10^23 kg.

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