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8_murik_8 [283]

2 years ago

13

A polyethylene rod exactly 10 inches long with a cross-sectional area of 0.04 in2 is used to suspend a weight of 358 lbs-f (poun

ds-force). Given the tensile modulus for this polymer is 25,000 psi and the viscosity is 1 × 109 psi-sec, calculate the length of the rod, in inches, 1 hour(s) after loading. Answer Format: X.XX Unit: inches

1 answer:

Nadya [2.5K]2 years ago

7 0

Answer:

Final length of the rod = 13.90 in

Explanation:

Cross Sectional Area of the polythene rod, A = 0.04 in²

Original length of the polythene rod, l = 10 inches

Tensile modulus for the polymer, E = 25,000 psi

Viscosity, $\eta = 1*10^{9} psi -sec$

Weight = 358 lbs - f

time, t = 1 hr = 3600 sec

Stress is given by:

$\sigma = \frac{Force}{Area} \\\sigma = \frac{358}{0.04} \\\sigma = 8950 psi$

Based on Maxwell's equation, the strain is given by:

$strain = \sigma ( \frac{1}{E} + \frac{t}{\eta} )\\Strain = 8950 ( \frac{1}{25000} + \frac{3600}{10^{9} } )\\Strain = 0.39022$

Strain = Extension/(original Length)

0.39022 = Extension/10

Extension = 0.39022 * 10

Extension = 3.9022 in

Extension = Final length - Original length

3.9022 = Final length - 10

Final length = 10 + 3.9022

Final length = 13.9022 in

Final length = 13.90 in

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Answer:

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konstantin123 [22]

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Explanation:

given data

recording done = 2 performances

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to find out

recordings sound the same and why

solution

as per given in

1st show is sold out it mean in this case concert hall is full so that recording sound should be high here

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