Question 65 – A differential equation is given as y” + 5y’ + 6y = 0, y(0) = 2 and y’(0) = 3. By using Laplace transform, an engineer has correctly produced the equation L {y} = (2s + 13) / [(s + 2)(s + 3)] = A / (s + 2) + B (s + 3). (a) Find the values of A and B. (b) The inversed Laplace transform of 1 / (s + a) is given by exp (-at) where a is a constant. If the statement : L {y} = 9 L { exp (-2t) } - 7 L { exp (-3t) } is correct, find the equation of y as a function of t as a solution to the differential equation stated in the beginning of this question. When L {d} = 9 L {b} - 7 L {c}, then d = 9b - 7c with b, c and d are unknowns.

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Corenuts technology interview questions

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X is strong but has a very low density (1% of traditional earth materials.) and hence light weight. It is a recyclable material. The compression behaviour of X is strain rate dependent. Higher strain rates result in higher initial modulus and higher compression strength. It can also withstand unlimited number of cycling loading provided the repetitive loads are kept below 80% of the compressive strength. The internal structure of the material includes air-traps which make it poor heat conductor. X is non- biodegradable and chemically inert in both soil and water. Most acids and their water solutions do not attack it; however strong oxidizing acids do. Solvents which attack X include esters, ketones, ethers, aromatic and aliphatic hydrocarbons and their emulsions, among others. It does not support bacterial/fungal growth as well .It also has significant acoustic properties and effectively reduces the transmission of airborne sound. X is combustible and should not be exposed to open flame or other ignition sources. Combustion products are carbon monoxide, carbon dioxide, water and soot. Long-term exposure to sunlight causes yellowing and a slight embrittlement of the surface due to ultraviolet light. X is able to withstand the rigours of temperature cycling, assuring long-term performance.

0 Answers   Ford,

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We have some pieces of metals that have been 'powder coated', how does that work?

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i want pattern of ONGC Written examination

13 Answers   IOCL, ONGC, Reliance,

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What are the three classes of organic solvents?

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I am currently doing my btech in computer science in Coimbatore.I had intererest to do btech in chemical enginerring but couldnt get a seat. Now what are my options ,scope and future if i take mtech in chemical enginerring? And can i apply for any deemed colleges for mtech chemical enginerring through gate taking my present state into consideration(btech in cse and mtech in chemical enginerring)

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respected sir,i have been selected in the written examination prelim (CHEMICAL) of RINL(RASHTRIYE ISPAT NIGAM LTD.) held on 20 JUNE, So please tell me which type of questions will be asked in 2nd stage written exam. plz send me last 2-3 years questions asked in RINL(written exam).

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Question 94 - The resolution of separation, Rs for chromatography is given by the formula Rs = (difference in retention time) / (average width at the base). In a chromatogram, 3 peaks a, b and c are found. Average widths W at the bases of the solutes are : Wa = 20 s, Wb = 40 s, Wc = 30 s. Resolutions of separation, Rs for solutes b and c in comparison to a are 2 and 4 respectively. The differences in retention times T for b and c in comparison to a are (Tb - Ta) and (Tc - Ta), Ta = Tc - Tb : (a) Form 2 equations involving Rs as a function of Wa, Wb, Wc, Ta, Tb and Tc. (b) Find the values of Ta, Tb and Tc.

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What is the meaning of the critical speed of a turbine, and what are its effects on the shaft line

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Explain what are the affinity laws associated with dynamics pumps?

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Question 8 - A local utility burns coal having the following composition on a dry basis : Carbon (C) 83.05 %, hydrogen (H) 4.45 %, oxygen (O) 3.36 %, nitrogen (N) 1.08 %, sulfur (S) 0.7 % and ash 7.36 %. Calculate the ash free composition of the coal with reference to C, H, O, N and S.

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