In the javelin throw at a track-and-field event, the javelin is launched at a speed of 23 m/s at an angle of 34° above the horizontal. as the javelin travels upward, its velocity points above the horizontal at an angle that decreases as time passes. how much time is required for the angle to be reduced from 34° at launch to 16°?

0.75s

Explanation:

The speed of the javelin has two components, the x-component and the y-component. The x-component will remain constant, but the y-component will be affected by the gravitational acceleration. In order for the angle to be reduced to 16°, the y-component divided by the x-component should be equal to tan(16°):

And, knowing that: