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2 years ago

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Estimate (a) the maximum, and (b) the minimum thermal conductivity values (in W/m-K) for a cermet that contains 76 vol% carbide

particles in a metal matrix. Assume thermal conductivities of 30 and 67 W/m-K for the carbide and metal, respectively.

1 answer:

Georgia [21]2 years ago

8 0

Answer:

The answer is below

Explanation:

Given that:

Volume of carbide ( $V_{C}$ ) = 76% = 0.76, Volume of Nickel ( $V_{M}$ ) = 100% - 76% = 24% = 0.24, thermal conductivities of carbide ( $E_{C}$ ) = 30 W/m-K and thermal conductivities of meta. ( $E_M$ ) = 67 W/m-K

a) The maximum thermal conductivity is given by:

Max = $E_CV_c+E_mV_m=(0.76*30) + (0.24*67) = 38.88\ W/mK$

b) The minimum thermal conductivity is given by:

Min = $\frac{E_ME_C}{E_MV_C+E_CV_M}=\frac{30*67}{(0.76*67)+(0.24*30)}=34.58\ W/mK$

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Answer:

4.5kg/min

Explanation:

Given parameters

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if we take

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The temperature of the mixed exit stream given as

$T_3m_3 = T_2m_2 +T_1m_1\\\\17 ( 3 + m_2) = 7 \times m_2 + 32 \times 3\\\\51 + 17 m_2 = 7 m_2 + 96\\\\10 m_2 = 96 - 51\\\\m_2 = 4.5 kg/min\\\\\\\\$

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3 years ago

Two resistors, A and B, individually connect to a 9V battery. A student notices that resistor A is warmer than resistor B. Which

dybincka [34]

Answer:

Resistor B

Explanation:

Since resistance is the opposition to the flow of current in a circuit,

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The energy dissipated in each resistor can be calculated as

$E=\frac{1}{2}IR^{2}t$ .

from the formula we can conclude that the energy value will be higher for the resistor with small resistance value. hence more heating effect which will cause it to be warm.

Also when connected individually the current flow from the voltage source will pass through the resistor which when we calculate the energy dissipated, the resistor with smaller value will be higher because it will draw more current which will in turn lead to a heating effect and cause the resistor to be warm. Hence we can conclude that the resistance B has greatest resistance value.

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2 years ago

Design an op amp circuit to average the input of six sensors used to measure temperature in restaurant griddles for a large fast

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Answer:

See the attached file for the design.

Explanation:

Find attached for the explanation.

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3 years ago

) An ammonia nitrogen analysis performed on a wastewater sample yielded 30 mg/L as nitrogen. If the pH of the sample was 8.5, de

Delicious77 [7]

Answer:

$NH_4^+ = 2.5 mg/lt$

Explanation:

Given data:

Ammonia Nitrogen 30 mg/L

pH = 8.5

-log[H +] = 8.5

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$NH_4 ^{+} ⇄ H^{+} + NH_3$

Rate constant is given as

$K_a = \frac{[H^{+}] [NH_3]}{NH_4^{+}}$ ...........1

$K_a = 5.6 \times 10^{-10}$

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from equation 1 we have

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3 years ago

An industrial system is rated at 600 v the system includes a partially exposed terminal block thats mounted on a bulkhead a new

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Answer:

10 ft or 3.048 m (for unqualified person)

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For a unqualified person:

The minimum approach distance is 10 ft or 3.048 m

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Since 600V lies in the above range hence it is applicable on 600V.

OSHA has developed a full list of minimum approach distance according to the level of voltages (50V to 72000V)

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