question_answer 55)

                  In dealing with motion of projectile in air, we ignore effect of air resistance on motion. This gives trajectory as a parabola as you have studied. What would the trajectory look like if air resistance is included? Sketch such a trajectory and explain why you have drawn it that way.

Answer:

                  When air resistance is neglected, the trajectory of the projectile is shown by a dotted curve as shown in Figure. However, when air resistance is taken into account, a part of its energy is utilized to overcome the force of friction and hence maximum height attained by the projectile decreases. Moreover, the horizontal component of the velocity of the projectile decreases continuously, so the projectile falls steeper than it rises up. The trajectory of such projectile is shown by solid curve.