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 loudspeakers, 5.5 m apart and facing each other, play identical sounds of the same frequency. you stand halfway between them, where there is a maximum of sound intensity. moving from this point toward one of the speakers, you encounter a minimum of sound intensity when you have moved 0.33 m . assume the speed of sound is 340 m/s. part a) what is the frequency of the sound? part b) if the frequency is then increased while you remain 0.21 m from the center, what is the first frequency for which that location will be a maximum of sound intensity? express your answer to two significant figures and include the appropriate units.