Aconcert loudspeaker suspended high off the ground emits 29.0 w of sound power. a small microphone with a 0.500 cm2 area is 55.0 m from the speaker. how much sound energy impinges on the microphone each second?

The man of mass m1 and the woman of mass m2 are standing on opposite ends of the platform of mass m0 which moves with negligible friction and is initially at rest with s = 0. the man and woman begin to approach each other. derive an expression for the displacement s of the platform when the two meet in terms of the displacement x1 of the man relative to the platform.