Answer:
f = 91.1 Hz
Explanation:
As we know that it is given here that wavelength of sound in platinum is same as the wavelength of sound in air
so we can use the formula of wavelength in two mediums
[tex]\frac{speed}{frequency} = \frac{speed}{frequency}[/tex]
now it is given that
[tex]v_{air} = 340 m/s[/tex]
[tex]v_{pt} = 2800 m/s[/tex]
frequency of sound in platinum is 750 Hz
now frequency of sound in air = f
now from above formula
[tex]\frac{340}{f} = \frac{2800}{750}[/tex]
[tex]f = 91.1 Hz[/tex]
