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Question
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.
Solution
When we are dealing with projectile motion generally we neglect air resistance. But if air resistance is included the horizontal component of velocity will not be constant and obviously trajectory will change.
Due to air resistance, particle energy as well as the horizontal component of velocity keep on decreasing making the fall steeper than the rise as shown in the figure.
When we are neglecting the air resistance path was symmetric parabola (OAC). When air resistance is considered path is an asymmetric parabola (OAB).
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