NOTE: There are 9 Questions in all.
· Question 1 is compulsory and carries 20 marks. Answer to Q. 1. must be written in the space provided for it in the answer book supplied and nowhere else.
· Out of the remaining EIGHT Questions answer any FIVE Questions. Each question carries 16 marks.
· Any required data not explicitly given, may be suitably assumed and stated.
Q.1 Choose the correct or best alternative in the following: (2x10)
a. The solution of the partial differential equation is
(A)
(B)
(C)
(D)
b. When a vibrating string has an initial velocity, its initial conditions are
(A) (B)
(C) (D) None of these
c. Image of under the mapping w = 1/z is
(A) 2 Im w + 1 = 0 (B) 2 Im w – 1 = 0
(C) 2 Rl w + 1 = 0 (D) 2 Rl w – 1 = 0
d. The value of is equal to
(A) –1 (B) 1
(C) 2 (D) 0
e. The invariant points of the transformation are given by
(A) (B)
(C) 0 (D)
f. In a Poisson Distribution if 2P(x = 1) = P(x=2), then the variance is
(A) 4 (B) 2
(C) 3 (D) 1
g. If V(X)=2, then V(2X+3) is equal to
(A) 6 (B) –8
(C) 8 (D)
h. is equal to
(A) 0 (B) –1
(C) (D)
i. If at (1,–2,–1) is equal to
(A) (B)
(C) (D)
j. If is such that then is called
(A) irrotational (B) solenoidal
(C) rotational (D) none of these
Answer any FIVE Questions out of EIGHT Questions.
Each question carries 16 marks.
Q.2 a. A bar 100 cm. long with insulated sides has its ends kept at 00C and 1000C until steady state conditions prevail. The two ends are then suddenly insulated and kept so. Find the temperature distribution. (8)
b. Solve by method of separation of variables . (8)
Q.3 a. X is a continuous random variable with probability density function given by
find the standard deviation and also the mean deviation about the mean for the random variable X. (8)
b. A car hire firm has two cars which it hires out day by day. The number of demands for a car on each day is distributed as a Poisson. Distribution with mean 1.5. Calculate the proportion of days on which no car is used and the proportion of days on which some demand is refused. (given that ) (8)
Q.4 a. A string is stretched between the fixed points (0,0) and (l,0) are released at rest from the initial deflection is given by find the deflection of the string at any time t. (8)
b. If r and have their usual meanings and is a constant vector, prove that . (8)
Q.5 a. Show that the vector field is conservative. Find its scalar potential and the work done in moving a particle from (-1,2,1) to (2,3,4). (8)
b. Find the values of constants and so that the surfaces intersect orthogonally at the point (1,-1,2). (8)
Q.6 a. The cylinder intersects the sphere . Find the surface area of the portion of the sphere cut by the cylinder above the yz plane and within the cylinder. (8)
b. Use the Divergence theorem to evaluate taken over the surface of the sphere , where l, m, n are the direction cosines of the external normal to the sphere. (8)
Q.7 a. Show that the function is analytical everywhere except on the half line . (8)
b. If u is a harmonic function, then show that is not a harmonic function, unless u is a constant. (8)
Q.8 a. Evaluate the integral , traversal counter clockwise. (8)
b. Obtain the first three terms of the Laurent series expansion of the function about the point z = 0 valid in the region . (8)
Q.9 a. Using complex integration, compute . (8)
b. Show that the bilinear transformation transforms the real axis in the z plane onto a circle in the w plane. Find the center and radius of the circle in the w plane. Find the point in the z plane which is mapped onto the centre of the circle in the w plane. (8)