Two submarines are underwater and approaching each other head-on. Sub A has a speed of 18 m/s and sub B has a speed of 14 m/s. Sub A sends out a 1040-Hz sonar wave that travels at a speed of 1522 m/s.
(a) What is the frequency detected by sub B (to the nearest Hz)?
(b) Part of the sonar wave is reflected from B and returns to A. What frequency does A detect for this reflected wave (to the nearest Hz)?