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sleet_krkn [62]

2 years ago

5

Calculate the number of vacancies per cubic meter for some metal, M, at 749°C. The energy for vacancy formation is 0.86 eV/atom,

while the density and atomic weight for this metal are 5.94 g/cm3 (at 749°C) and 80.09 g/mol, respectively.

1 answer:

kogti [31]2 years ago

5 0

Answer:

Number of Vacancies = 1.22E23

Explanation:

Given

Energy for formation = 0.86 eV/atom (Q)

Density = 5.94 g/cm³

Atomic weight = 80.09 g/mol

Temperature = 749°C = 1022K

Avogadro's Constant = 6.022E23 atoms/mol

Boltzmann constant = 8.62E-5 eV/K (k)

Determination of the number of vacancies per cubic meter in metal, M at 749C (1022 K) is given by:

N exp (-Q/kT)

Where N = 6.022E23 * 5.94/ 80.09

N = 4.47E22

So, Number of Vacancies = 4.47E22 exp (-0.86 / (8.62E-5 * 1022))

= 4.47E22 exp (-9.76)

= 1.2150719773211E23

Number of Vacancies = 1.22E23 ------ Approximated

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Answer:

Power output, $P_{out} = 178.56 kW$

Given:

Pressure of steam, P = 1400 kPa

Temperature of steam, $T = 350^{\circ}C$

Diameter of pipe, d = 8 cm = 0.08 m

Mass flow rate, $\dot{m} = 0.1 kg.s^{- 1}$

Diameter of exhaust pipe, $d_{h} = 15 cm = 0.15 m$

Pressure at exhaust, P' = 50 kPa

temperature, T' = $100^{\circ}C$

Solution:

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$0.1 = \frac{\frac{\pi d^{2}}{4}v_{i}}{0.2004}$

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$v_{i} = 3.986 m/s$

Now, eqn for compressible fluid:

$\rho_{1}v_{i}A_{1} = \rho_{2}v_{e}A_{2}$

Now,

$\frac{A_{1}v_{i}}{V_{1}} = \frac{A_{2}v_{e}}{V_{2}}$

$\frac{\frac{\pi d_{i}^{2}}{4}v_{i}}{V_{1}} = \frac{\frac{\pi d_{e}^{2}}{4}v_{e}}{V_{2}}$

$\frac{\frac{\pi \times 0.08^{2}}{4}\times 3.986}{0.2004} = \frac{\frac{\pi 0.15^{2}}{4}v_{e}}{3.418}$

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$P_{out} = -\dot{m}W_{s}$

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The steel 4140 steel contains 0.4% C, however, it shows higher yield strength and ultimate strength than that of the 1045 (0.45%

Aleonysh [2.5K]

Answer:

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Explanation:

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and these elements which are present in 4140 steel they increase yield strength and ultimate strength of steel

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Answer:

Following are the proving to this question:

Explanation:

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using the energy equation for entry and exit value :

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