Not right on time
In an imaginary atmosphere, the air exerts a small force on any particle in the direction of the particle's motion. A particle of mass projected upward takes time in reaching the maximum height and time in the return journey to the original point.
Which of the following must be true?
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1 solution
Since the air is exerting a force upwards during its trip to the maximum height, and gravity is still exerting a force downwards, the net force in the downward direction is less than the gravitational force (we assume a net force downwards otherwise there would be no maximum height).
On the particle's decent, it has both gravity and the air force both exerting in the downwards direction, meaning there is a net force greater than the gravitational force.
Since there is less net force during the ascent, it takes longer to reach the peak, meaning t > T