Question

a projectile is fired with an initial speed of 2000 m/s at an angle 21 degrees above the horizontal. if air resistance is neglected , what is the velocity in m/s at the highest point of trajectory ?

Answer 1

In projectile motion, there will be gravity acting in y direction (or vertical), but no force will be there in x direction(or horizontal). Therefore, only the velocity in y direction will change and the velocity in x direction will remain same as it was before.

Here at the highest point of trajectory, the velocity in the y direction will be zero and the x component velocity will remain same as before.

Therefore, Velocity at the highest point of trajectory = Velocity in x-direction

$\newline = 2000*\cos21 = 2000*0.934 = 1867.16 m/s.$

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