Page 63 - Engineering Mathematics Workbook_Final
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Vector Calculus
                       −
                                            −
                   (a)  8               (b)  4                         (c)     r   dr =  0  for every piece wise
                                                                              C
                   (c) 4        (d) 8                                  smooth closed curve C in D.

                                              [JAM 2008]                 (d) The differential equation
                                                                              +
                                                                          pdx qdy  is exact in D.
                                 ) xy +
                                              −
                                                 2 2
                       T x
            52.    Let  ( , , y z =    2   2z x z  be
                                                                                                    [JAM 2009]
                   the temperature at the point (x, y, z). The
                   unit vector in the direction in which the      54.    The value of C for which there exists a
                   temperature decreases most rapidly at                 twice differentiable vector field F  with
                          )
                   (1,0, 1 −  is ________
                                                                                              +
                                                                         curl  F = 2xi −  7y j czk  is _______
                          1  $    2  $
                   (a)  −    i +     k                                   (a) 0                 (b) 2
                           5       5
                                                                         (c) 5                 (d) 7
                        1  $    2  $
                   (b)     i −     k                                                                [JAM 2009]
                         5       5
                                                                                        x $
                                                                                                           $
                                                                                                   $
                                                                                                 2
                                                                                         2
                                                                                                          2
                                                                                                         x
                                                                                                 x
                        2   $     3   $    1   $                  55.    Let  F = 2xyze i +   ze j +   ye k  be
                   (c)      i +       j +      k                         the gradient of a scalar function. The
                        14        14       14
                                                                                       
                           2   $    3   $     1  $                    value of    F dr  along the oriented
                                                    
                                                     
                   (d)  −     i +      j +      k                               C
                           14       14        14                       path L from (0, 0, 0) to (1, 0, 2) and then
                                                                         to (1, 1, 2) is ______
                                              [JAM 2009]
                                                                         (a) 0                 (b) 2e
                                                      $
                                                    )
            53.    Suppose V =   P ( , x y )i +  $  q ( , x y j  is                                2
                                                                         (c) e                 (d) e
                   a continuously differentiable vector field
                                           2
                   defined in a domain in  R . Which one                                            [JAM 2010]
                   of the following statements is not                    Let  F =     +     −
                   equivalent to the remaining ones?              56.             xyi y j yzk  denote the
                                                                         force field on a particle traversing the
                   (a) There exists a function  ( ,x y  ) such          path L from (0, 0, 0) to C (1, 1, 1) along
                                                                         the curve of intersection of the cylinder
                         
                                      )
                                                                           =
                                                                               2
                   that     =  p ( ,x y  and                              y x  and the plane  z x. The work
                                                                                                =
                         x
                      =  q ( ,x y  for all ( , x y                    done by F  is __________
                                 )
                                               ) R
                     y
                                                                                                  1
                                                                         (a) 0                 (b)
                         p    q                                                                 4
                   (b)     =      holds at all points of D.
                         y    x

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