What is the relationship between Young's modulus and bulk modulus in tin?

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Young's modulus for tin is given as 4.5x10^10, and the speed of sound in tin is measured at 2.73 km/s. The relationship between bulk modulus and Young's modulus is discussed, with the bulk modulus being approximately three times the Young's modulus. When applying the formula for sound velocity, it is noted that using Young's modulus instead of bulk modulus yields a correct answer from the provided choices. The discussion concludes that for longitudinal sound waves in thin rods, the speed of sound is indeed dependent on Young's modulus rather than bulk modulus.
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1. The Young's modulus for tin is 4.5x10^10. If the speed of sound in tin is measured to be 2.73km/s , find its density in (kg/m^3) .

a)6.05x10^3
b)23.8x10^3
c)6.35x10^3
d)24.5x10^3
e)6.65x10^3

, E(tin)=4.5x10^10 ,speed of sound in tin=2.73km/s




2. v=sqrt(B/density) -where B is bulk modulus



3. if i substitute B as young's modulus I get answer a) in the choices.


What is difference between bulk modulus and young's modulus and if there is what relation relates them.Thanks.
 
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Bulk modulus = 3*young's modulus.
 
But when i substitute v=sqrt(3Y/density)=sqrt(B/density) i don't get an answer from choices while i do if i substitute v=y/density.is it possible that in sound waves the velocity is proportional to youngs modulus instead of bulk modulus as in other cases.From serway :"For longitudinal sound waves in a solid rod of material, for example, the speed of
sound depends on Young’s modulus Y and the density !. Table 17.1 provides the speed
of sound in several different materials"

please advise.:)
 
any idea anybody?:confused:
 
While calculating the velocity of sound in solid, if the solid is a thin rod, the bulk modulus is replaced by Young's modulus.
 
thanks very much.
 
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