1. A water wave passing a point causes a cork to bob up and down through a total distance of 1 m, completing one cycle every 1.5 sec. It is noted that the wave crests are 4 m apart. What is the frequency of the wave?
2. The smallest object which can be resolved with a given frequency of ultrasound in a diagnostic scaner is on the order of the wavelength of the ultrasound used. If 20 MHz ultrasound is used for a scan of the eye, and the speed of the wave is 1500 m/s, how small an object coud be detected in the eye?