Question 65 – A differential equation is given as y” + 5y’ + 6

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.

Question Posted / kang chuen tat (malaysia - pen

1 Answers
2236 Views
I also Faced
E-Mail Answers

Question 65 – A differential equation is given as y” + 5y’ + 6y = 0, y(0) = 2 and ..

Answer / kang chuen tat (malaysia - pen

Answer 65 – (a) Let (2s + 13) / [(s + 2)(s + 3)] = [A (s + 3) + B (s + 2)] / [(s + 2)(s + 3)]. Then 2s + 13 = As + 3A + Bs + 2B = (A + B)s + (3A + 2B), then A + B = 2 and 3A + 2B = 13. Let 2A + 2B = 4 as first equation by doubling A + B = 2 and 3A + 2B = 13 as second equation, the difference of first and second equations will produce A = 9. When A = 9, B = 2 - A = 2 - 9 = -7. (b) Let d = y, b = exp (-2t) and c = exp (-3t), then y = 9 exp (-2t) - 7 exp (-3t). 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.

Is This Answer Correct ?

0 Yes

0 No

Post New Answer

More Chemical Engineering Interview Questions

wt is inhand salary in hpcl as a officer in research and development?????

0 Answers

where can i get previous question papers of GATE in chemical engineering

7 Answers CPCL,

Why is post-weld heat treatment sometimes necessary for welded vessels?

0 Answers Aramco,

ENGINEERING PHYSICS - EXAMPLE 30.4 : (a) Time evolution in Heisenberg picture, according to Ehrenfest theorem is m (d / dt) < r > = < p >, where m = mass, r = position, p = momentum of a particle. If v = velocity, prove that m < v > = < p >. (b) Lande g-factor is given by Gj = Gl [ J (J + 1) - S (S + 1) + L (L + 1) ] / [ 2J (J + 1) ] + Gs [ J (J + 1) + S (S + 1) - L (L + 1) ] / [ 2J (J + 1) ]. If Gl = 1 and under approximation of Gs = 2, prove by calculation that Gj = (3/2) + [ S (S + 1) - L (L + 1) ] / [ 2J (J + 1) ].

1 Answers

sir i am senthil B.Tech Chemical Engineer which book is refer for objective type questions?

2 Answers BARC, GATE,

viscosty of crude use for petroliun?

4 Answers ONGC,

What fluid first to be lined up in a heat exchanger whether hot or liquid?why?

2 Answers TCL,

What are the some common problems associated with dense phase pneumatic conveying?

0 Answers

i am going to appear vedanta written test so plz can any body suggest me for this on madhu.5393@gmail.com

0 Answers

1.How a chlorine leak is detected? 2.What would happen if excess chlorine is added to water in cooling tower?

3 Answers

Which one is process and why?( evaporation, vaporization, reactor, fluid flow)

5 Answers

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

0 Answers

For more Chemical Engineering Interview Questions Click Here