Q. Two speakers, one directly behind the other, are each generating a 275 Hz sound wave. What is the smallest separation distance between the speakers that will produce destructive interference at a listener standing in front of them? Assume that the speed of sound is 335 m/s.
Q. A 0.7 kg block of ice is sliding by you on a very slippery floor at 4 m/s. As it goes by, you give it a kick perpendicular to its path. Your foot is in contact with the ice block for 0.003 seconds. The block eventually slides at an angle of 27 degrees from its original direction (labelled in the diagram). The overhead view shown in the diagram is approximately to scale. The arrow represents the average force your toe applies briefly to the block of ice.
What is the unit vector in the direction of the block's momentum after the kick?