A standard frequency for tuning musical instruments is 440 Hz for the pitch of A, denoted A4. What is the length, in meters, of the steel rod that produces the pitch A4 as its fundamental longitudinal resonance?

frequency of tuning fork = 440 Hz

wave length λ = velocity of sound / frequency

= 343 / 440 m

=.7795 m

= 77.95 cm

λ = 77.95 cm

Let length of rod having fundamental wavelength of 77.95 cm be L

L = λ / 2

L = 77.95 / 2

= 38.975 cm.

length of rod = 38.975 cm.

= 0. 39 m