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Question
In a projectile motion the velocity
Options
is always perpendicular to the acceleration
is never perpendicular to the acceleration
is perpendicular to the acceleration for one instant only
is perpendicular to the acceleration for two instants.
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Solution
is perpendicular to the acceleration for one instant only
In projectile motion, velocity is perpendicular to acceleration only at the highest point. Here, velocity is along the horizontal direction and acceleration is along the vertically downward direction.
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