In a resonance tube, using a tuning fork of frequency 325Hz, the first two resonance lengths are observed at 25.4cm and 77.4cm. The speed of sound in air is In a resonance tube the first two resonance lengths are observed at 25.4cm and 77.4cm. The speed of sound in air is using a tuning fork of frequency 325Hz October 31, 2020 Category: Cengage NEET by C.P Singh , Chapter 17 - Sound Waves , Part 1 , Facebook Messenger WhatsApp Share this:TwitterFacebook Related