1. The problem statement, all variables and given/known data Two navigation beacons 60km apart transmit radio waves of wavelength 4000m. The signals start with the same phase and amplitude. A ship is midway between them and is sailing straight towards one of them. Describe what happens to the signals received on board the ship over the next 6km. 2. Relevant equations v=f x lambda ? 3. The attempt at a solution Um... I just don't really get it... I was thinking along the lines that there would 15 waves in the 60km....?