Answer / kang chuen tat (malaysia - pen

Answer 55 - (a) For the equation 3 dy / dt + 2y = 1, its Laplace transformation is 3 [ sY(s) - y(0) ] + 2Y(s) = 1 / s, 3 (sY - 1) + 2Y = 1 / s, 3sY - 3 + 2Y = 1 / s, 3sY + 2Y = 1 / s + 3, Y (3s + 2) = (1 + 3s) / s. Y = Y(s) = (1 + 3s) / [ s (3s + 2) ]. (b) Initial value theorem states that y(0) = sY(infinity), then 1 = s (1 + 3s) / [ s (3s + 2) ] = (1 + 3s) / (3s + 2) approaches 1 when the value of s approaches infinity. The checking is correct. The answer is given by Kang Chuen Tat; PO Box 6263, Dandenong, Victoria VIC 3175, Australia; SMS +61405421706; chuentat@hotmail.com; http://kangchuentat.wordpress.com.

CHEMICAL ENERGY BALANCE - EXAMPLE 11.5 : According to Margules Equation, P = x(1) p(1) g(1) + x(2) p(2) g(2) for a two-component mixture where P is bubble pressure, x is mole fraction, p is saturation pressure, g is constant given by ln g(1) = x(2) A x(2). Find the value of A as a constant when P = 1.08 bar, p(1) = 0.82 bar, p(2) = 1.93 bar in a 50 : 50 mole fraction mixture. Estimate the pressure required to completely liquefy the 30 : 70 mixture using the same equation, by proving P = 1.39 bar. Take note that ln g(2) = x(1) A x(1), ln g(1) = x(2) A x(2).

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Calculate the line size for a cooling water line with a volumetric flowrate of 1200m3/h of water. Density of water = 1000kg/m3

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hi all i have doe cheical engg, but i have to go for iob po interview so can anybody suggest me abt the kind of qns that can be asked.

0 Answers   Indian Overseas Bank,

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How are plate heat exchangers used in an ammonia refrigeration system?

1 Answers   HJ, Reliance,

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How can you control the ph level in our cooling water with respect to ammonia contamination?

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Difference between Synthetic foaming agents V/S Protien based foaming agent?

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ACCOUNTING AND FINANCIAL ENGINEERING - EXAMPLE 34.21 : The cost of building a biochemical processing plant is increasing due to inflation. Let I = inflation rate, R = nominal interest rate, r = real interest rate. According to Fisher Equation, (1 + r)(1 + I) = (1 + R). According to General Inflation Equation, R = r + I. (a) By assuming that both r and I are fairly small, prove by mathematical calculations that complicated Fisher Equation could be simplified into the General Inflation Equation. (b) By using 2 first order Taylor expansions in the linear approximation, namely 1 / (1 + x) ≈ (1 - x), (1 + x)(1 + y) ≈ 1 + x + y, show by mathematical calculations that (1 + r) = (1 + R) / (1 + I) could be approximated by r ≈ R - I.

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QUANTUM CHEMISTRY AND CHEMICAL ENGINEERING - EXAMPLE 31.7 : (a) The correct statement about both the average value of position (<x>) and momentum (<p>) of a 1-dimensional harmonic oscillator wavefunction is <x> = <p> = 1 - x. Find the value of x. (b) The probabilities of finding a particle around points A, B and C in the wavefunction y = f(x) are P(A), P(B) and P(C) respectively. Coordinates are A (3,5), B (4,-10) and C (6,7). Arrange P(A), P(B) and P(C) in term of a < b < c, when | y-coordinate | signifies the probability.

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why is cross over inlet provided in a furnace?

3 Answers   Essar,

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Mention some of the specialized grinding and crushing methods.

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What is the process of including heat exchangers in ammonia refrigeration system?

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FOOD ENGINEERING - QUESTION 23.2 : (a) A dryer reduces the moisture content of 100 kg of a potato product from 80 % to 10 % moisture. Find the mass of the water removed in such drying process. (b) During the drying process, the air is cooled from 80 °C to 71 °C in passing through the dryer. If the latent heat of vaporization corresponding to a saturation temperature of 71 °C is 2331 kJ / kg for water, find the heat energy required to evaporate the water only. (c) Assume potato enters at 24 °C, which is also the ambient air temperature, and leaves at the same temperature as the exit air. The specific heat of potato is 3.43 kJ / (kg °C). Find the minimum heat energy required to raise the temperature of the potatoes. (d) 250 kg of steam at 70 kPa gauge is used to heat 49,800 cubic metre of air to 80 °C, and the air is cooled to 71 °C in passing through the dryer. If the latent heat of steam at 70 kPa gauge is 2283 kJ / kg, find the heat energy in steam. (e) Calculate the efficiency of the dryer based heat input and output, in drying air. Use the formula (Ti - To) / (Ti - Ta) where Ti is the inlet (high) air temperature into the dryer, To is the outlet air temperature from the dryer, and Ta is the ambient air temperature.

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