You have a unknown tuning fork it hits its first resonance at 31 cm what is it frequency

Answer 1

c = γν

c = speed of light = ~ 3x10⁸ m/sec

λ = wavelength = 31 cm = 0.31 m

ν = frequency

3x10⁸ m/sec = 0.31 m x ν

ν = 3x10⁸ msec-1/0.31 m

ν = 9.7 sec-1 = 9.7 Hz