Q. An ultrasonic beam reflects off a tumor in an organ at an angle of 55 with a shift L = 4.7 cm.
If the speed of the wave is 10 % less in the organ than in the medium above, determine the depth of the tumor below the organ's surface.
Q. One billiard ball is shot east at 3.0 m/s. A second, identical billiard ball is shot west at 0.8 m/s. The balls have a glancing collision, not a head-on collision, deflecting the second ball by 90° and sending it north at 1.56 m/s. What are the speed and direction of the first ball after the collision?