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A rogue band of colonists on the moon declares war and prepares to use a catapult to launch large boulders at the earth. Assume that the boulders are launched from the point on the moon nearest the earth. For this problem you can ignore the rotation of the two bodies and the orbiting of the moon.1) What is the minimum speed with which a boulder must be launched to reach the earth? Hint: The minimum speed is not the escape speed. You need to analyze a three-body system.2) Ignoring air resistance, what is the impact speed on earth of a boulder launched at this minimum speed?

1 Answer

4 votes

Answer:

  • 2.3 km/s
  • 11 km/s

Step-by-step explanation:

The system is made up of three body system which are the boulder, earth and the moon also the sum of potential ad kinetic energies are assumed to be the same also note that the boulder was launched from the moon at an initial velocity

A ) Minimum speed of the boulder for it to reach the earth = 2.3 km/s

B) ignoring air resistance the impact speed on earth of a boulder launched at this minimum speed = 11 km/s

find attached the solution in details

A rogue band of colonists on the moon declares war and prepares to use a catapult-example-1
A rogue band of colonists on the moon declares war and prepares to use a catapult-example-2
A rogue band of colonists on the moon declares war and prepares to use a catapult-example-3
User Sean Routledge
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