On a frictionless horizontal surface, a person cannot propel themselves forward by pushing against the ground (like walking, running, or jumping) because there is no friction to provide an external reaction force in the horizontal direction. However, by sneezing, the person expels air in one direction. According to Newton's third law of motion, this action creates an equal and opposite reaction force on the person's body, propelling them in the opposite direction of the expelled air.
A person is standing on a frictionless horizontal ground. How can he move by a certain distance on this ground?
Asked in UPSC CDS 2 2017 · Topic: Mechanics (Newton's Laws of Motion and their applications)
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