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SCORPION-xisa [38]
3 years ago
7

A composite wall is to be used to insulate a freezer chamber at -350C. Two insulating materials are to be used with conductiviti

es of 0.04 W/mK and 0.1 W/mK. If the outside surface temperature of the inner layer (0.04 W/mK) should not go below zero and if the exposed surface temperature should not go below (the expected wet bulb temperature) 220C determine the insulation thicknesses. The heat gain is to be limited to 10 W/m^2. Also estimate the value of convection coefficient at such a situation. Outside is at 250C.
Engineering
1 answer:
choli [55]3 years ago
7 0

Answer:

thickness1=1.4m

thickness2=2.2m

convection coefficient=0.33W/m^2K

Explanation:

you must use this equation to calculate the thickness:

L=K(T2-T1)/Q

L=thickness

T=temperature

Q=heat

L1=0.04*(0--350)/10=1.4m

L2=0.1(220-0)/10=2.2m

Then use this equation to calculate the convective coefficient

H=Q/(T2-T1)

H=10/(250-220)=0.33W/m^2K

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A light bar AD is suspended from a cable BE and supports a 20-kg block at C. The ends A and D of the bar are in contact with fri
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Answer:

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3 years ago
Say you have a random, unordered list containing 4096 four-digit numbers. Describe the most efficient way to: sort the list and
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Answer:

Answer explained below

Explanation:

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So we need to sort a list of integers, where each integer lies between [0,9999].

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--------------------------------------------------------------------------------

Psuedo Code:

countSort(int numList[]) {

int count[10000];

count[i] = 0; for all i;

for(int num in numList){

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}

--------------------------------------------------------------------------------

Searching in this count array will be just O(1).

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Case 2: it was not present:

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Search: O(1)

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