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Natasha2012 [34]

3 years ago

15

The density of aluminum is 2.7 × 103 kg/m3 . the speed of longitudinal waves in an aluminum rod is measured to be 5.1 × 103 m/s.

what is the value of young's modulus for this aluminum?

1 answer:

andrey2020 [161]3 years ago

5 0

<span>The speed of longitudinal waves, S, in a thin rod = âšYoung modulus / density , where Y is in N/m^2. So, S = âšYoung modulus/ density. Squaring both sides, we have, S^2 = Young Modulus/ density. So, Young Modulus = S^2 * density; where S is the speed of the longitudinal wave. Then Substiting into the eqn we have (5.1 *10^3)^2 * 2.7 * 10^3 = 26.01 * 10^6 * 2.7 *10^6 = 26.01 * 2.7 * 10^ (6+3) = 70.227 * 10 ^9</span>

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2 years ago

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Explanation:

Considering the first question

From the question we are told that

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Considering the first wire

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Generally the current in the first wire is

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The cross-sectional area of the second wire is

$A_1 = 19 * \pi r^2$

=> $A_1 = 19 *3.142 * (0.000306)^2$

=> $A_1 = 5.5899 *10^{-6} \ m^2$

Generally the current is

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=> $I_2 = 1750 * 5.5899 *10^{-6}$

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Considering question two

From the question we are told that

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Generally the resistance of the first wire is mathematically represented as

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=> $R_1 = 0.0189 \ \Omega$

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