A flute is designed to play middle C (262 Hz) as the fundamental frequency when all the holes are covered. The length of the flute is 0.655 m. Assume the air temperature is 20°C. How far from the end of the flute should the hole be that must be uncovered to play F above middle C (349 Hz)?
I used... Speed of sound in air= 343 m/s, speed of sound in helium= 1005 m/s
and got 0.4914040115 cm but it was marked wrong.