This question deals with projectile motion, which is a motion on both the x-axis and y-axis, simultaneously. The total time of flight of the projectile trajectory is given, while the time to reach the highest point of the projectile is required to be found.
The projectile will reach the highest point in "3 seconds".
The total time of flight of a projectile is the time during which the projectile remains in the air. For a projectile motion that ends up on the same horizontal level, from where it started, the time to reach the highest point, is equal to half of the total time of flight.
In other words, the projectile motion takes the same time, to go from the starting level to the highest point (i.e upward motion), as the time taken to reach the starting level from the highest point (i.e downward motion).
[tex]t = \frac{1}{2}T[/tex]
where,
t = time to reach the highest point = ?
T = total time of flight = 6 seconds
Therefore,
[tex]t - \frac{1}{2}(6\ seconds)[/tex]
t = 3 seconds
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