question_answer 38)

  A girl is carrying a school bag of 3 kg mass on her back and moves 200 m on a leveled road. The work done against the gravitational force will be (a)                          (b)                                   (c)                                (d)zero

Answer:

  (d) We know that, work done Force on school bag makes an angle 90° from the road.     i.e.,                                                                      Hence, work done against the gravitational force is zero.