What is the wave speed in the bridge?

[CMATT]

Homework Statement

A certain pedestrian bridge in England resonates like a string fixed at both ends. If the bridge is 73.0 m long and its fundamental resonance is at 0.600 Hz, what is the wave speed in the bridge?

Homework Equations

Velocity = (frequency)(wavelength)

The Attempt at a Solution

wavelength = 73.0 m
frequency = .600 Hz
velocity = find it

v = (.600)(73.0)
v = 43.4 = 44 m/s

I got this wrong on my hw, I thought this was how to do it? Could someone please show me what I am doing wrong?
Thank you for your help

 

[Potatochip911]

Homework Statement

A certain pedestrian bridge in England resonates like a string fixed at both ends. If the bridge is 73.0 m long and its fundamental resonance is at 0.600 Hz, what is the wave speed in the bridge?

Homework Equations

Velocity = (frequency)(wavelength)

The Attempt at a Solution

wavelength = 73.0 m
frequency = .600 Hz
velocity = find it

v = (.600)(73.0)
v = 43.4 = 44 m/s

I got this wrong on my hw, I thought this was how to do it? Could someone please show me what I am doing wrong?
Thank you for your help

Note that the fundamental resonance is not the same thing as frequency.

 

[DrewDrewDrew]

Multiply by 2.

The "fundamental resonance" is when the bridge is resonating at only half a wavelength. To correct for this to find the velocity, multiply the length of the bridge by 2.