The Captain of a Spaceship Orbiting Planet X Discovers That $410 \mathrm {~km}$

question 10

Multiple Choice

The captain of a spaceship orbiting planet X discovers that to remain in orbit at $410 \mathrm {~km}$ from the planet's center, she needs to maintain a speed of $68 \mathrm {~m} / \mathrm { s }$ What is the mass of planet X? (G = 6.67 × 10^-11 N ? m²/kg²)

• A)2.8 × 10¹⁹ kg
• B)4.2 × 10¹⁷ kg
• C)2.8 × 10¹⁶ kg
• D)4.2 × 10¹⁴ kg

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