## College Physics (4th Edition)

A passenger in the oncoming boat hears a frequency of $346.5~Hz$
We can use the equation for the Doppler effect when both the observer and the source are moving toward each other: $f_o = \left(\frac{v+v_o}{v-v_s}\right)~f_s$ $f_o = \left(\frac{343~m/s+15.6~m/s}{343~m/s-20.1~m/s}\right)~(312~Hz)$ $f_o = 346.5~Hz$ A passenger in the oncoming boat hears a frequency of $346.5~Hz$.