projectile at any instant during its flight has velocity 5 metre per second at 30 degrees above the horizontal - Physics - Motion In A Plane

Question

projectile at any instant during its flight has velocity 5 metre
per second at 30 degrees above the horizontal how long after this
instant will it be moving at right angle to the given direction

Bhushan Khairnar · Answer

Here's the ans
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projectile at any instant during its flight has velocity 5 metre per second at 30 degrees above the horizontal. how long after this instant will it be moving at right angle to the given direction