question_answer 37)

  An iron sphere of mass 10 kg has the same diameter as an aluminium sphere of mass 3.5 kg. Both spheres are dropped simultaneously from a tower. When they are 10 m above the ground, they have the same (a) acceleration                 (b) momenta                     (c) potential energy         (d) kinetic energy

Answer:

  (a) When both spheres are dropped simultaneously from a tower, they have same acceleration. Because, during free fall acceleration of body becomes equals to  and 'g' depends on mass of earth and radius of earth i.e.,