Question 106 - In a wavefunction, let P(x) = A cos kx + B sin kx. By using the boundary conditions of x = 0 and x = l, where P(0) = P(l) = 0, prove by mathematical calculation that P(x) = B sin (npx / l) where p = 22 / 7 approximately, n is a rounded number. A, B and k are constants.

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Question 33 – By using Excel program either on laptop or desktop PC, solve the differential equation dy / dx = -2y + x + 4 with h = 0.005, initial values : x = 0, y = 1. The 4th order Runge-Kutta method provides : y(N + 1) = y(N) + (1/6) (k1 + 2k2 +2k3 + k4), k1 = h [ -2y(N) + x(N) + 4 ], k2 = h { -2 [ y(N) + k1 / 2 ] + x(N) + h / 2 + 4 }, k3 = h { -2 [ y(N) + k2 / 2 ] + x(N) + h / 2 + 4 }, k4 = h { -2 [ y(N) + k3 ] + x(N) + h + 4 }. What is the value of y at x = 0.5?

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how to calculate overall heat transfer coefficient in insulated pipeline? Please give a answer with formula

2 Answers   NPCIL,

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What are the some common causes of control valve noise?

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Explain how can you determine the proper pipe thickness for a slurry line?

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Are some heat transfer services more prone to tube vibration that others for a shell and tube exchanger?

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design calculations for reactor

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How does a tank-blanketing valve operate?

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Your favourite area of interest

7 Answers   Ambuja, CPCL, Genpact, Lilliput,

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ACCOUNTING AND FINANCIAL ENGINEERING - EXAMPLE 34.13 (CORRECTION) : (i) In the Present Value Multiplication Rule, let PV = present value, Ra = interest rate for first discount, A = duration for first discount; Rc = interest rate for second discount, C = duration for second discount. Let PV = [ 1 / (1 + Ra) ^ A ] [ 1 / (1 + Rc) ^ C ] where ^ is the symbol of power : 3 ^ 2 = 3 x 3, 2 ^ 3 = 2 x 2 x 2. (a) For discounts involving 8 % / year for 3 years and 10 % / year for 9 years, find the value of PV. (b) If Re = interest rate for third discount, E = duration of third discount, form a mathematical equation of PV as a function of A, C, E, Ra, Rc, Re. Note : Discounts are available in the purchase of certain biochemical engineering instruments. (ii) Let R = nominal interest rate related to growth rate of money, r = real interest rate related to growth rate of purchase power. If I = inflation, where the unit of R, r and I is %, find the mathematical relationship of r as a function of R and I.

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What is the difference between coagulation and flocculation in water treatment plant?

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ELECTRICAL TECHNOLOGY - EXAMPLE 16.2 : In a selection of suitable heating equipment for drying of crystals of biochemical, the one of the lowest current consumption will be chosen for safety consideration. Selection is available : (A) 120 V microwave oven 1800 W. (B) 240 V conventional oven 11000 W. Which one should be chosen and why?

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