Final answer:
The beat frequency heard in the station is 73.91 Hz.
Step-by-step explanation:
To calculate the beat frequency heard in the station, we need to consider the Doppler effect. The beat frequency is the difference between the frequency of the moving tuba and the frequency of the stationary tuba.
Given that the frequency of the moving tuba is 75 Hz and the train is approaching the station at a speed of 5.0 m/s, we can use the Doppler effect equation:
f (beat) = f(stationary) - f(moving) = 75 Hz - (75 Hz * (5.0 m/s / 343.00 m/s)) = 75 Hz - 1.09 Hz = 73.91 Hz