question_answer 36)

  In case of negative work,  + the angle between the force and displacement is (a) 0                                       (b)                                  (c)                                   (d)

Answer:

  (a) Work done Work done at                                                                              W = F. d For angle Work done is positive,- so it is not true. . (b) We know that work done, Work done at                                                                                                                                                  For angle , work done is positive, so it is not true. (c) We know that work done,   Work done at             So, it is not true. (d) Work done at , For negative work, the angle between the force and displacement should be . (i.e., force and displacement are anti parallel to each other) So, it is true.