Arogue 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.

part a:

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.

part b:

ignoring air resistance, what is the impact speed on earth of a boulder launched at this minimum speed?

Two forces produce equal torques on a door about the door hinge. the first force is applied at the midpoint of the door; the second force is applied at the doorknob. both forces are applied perpendicular to the door. which force has a greater magnitude?

The astronauts on the space shuttle flights experienced an acceleration of 29 m/s2 (about 3 "g's") during lift-off. what upward force must the astronaut's seat apply to the astronaut in order to cause this acceleration? assume the astronaut's mass is 70 kg, and compute this force when the acceleration is near the earth's surface so their weight equals latex: mg m g .

On a hot saturday morning while people are working inside, the air conditioner keeps the temperature inside the building at 22degreesc. at noon the air conditioner is turned off, and the people go home. the temperature outside is a constant 33degreesc for the rest of the afternoon. if the time constant for the building is 4 hr, what will be the temperature inside the building at 4 : 00 font size decreased by 2 upper p . font size decreased by 2 upper m .? at 6 : 00 font size decreased by 2 upper p . font size decreased by 2 upper m .? when will the temperature inside the building reach 24degreesc? 324281