Amechanical high-speed bat is flying along a path perpendicular to a wall. it emits a sound with a frequency f0 . the night is clear and the air is still. let the speed of sound waves in the still air be vs . the bat hears a sound wave reflected from the wall with a frequency fnew . from this information one can determine the speed vbat at which the bat is flying. install a detector at the wall. 0 bat f v what is the detected frequency? 1. f1 = vs + vbat vs f0 2. f1 = vs vs − vbat f0 3. f1 = vs vs + vbat f0 4. f1 = vs + vbat vs − vbat f0 5. f1 = 2 vs vs − vbat f0 6. f1 = vs − vbat vs f0 7. f1 = vs − vbat vs + vbat f0 8. f1 = f0 9. f1 = 2 vs vs + vbat f0