Velocity and Acceleration Parallel?

AI Thread Summary
In projectile motion, when an object is thrown at an angle, its velocity has both horizontal and vertical components, while acceleration remains directed downward due to gravity. During the upward motion, the velocity is positive and acceleration is negative, indicating a decrease in speed. At the peak of the trajectory, the velocity is momentarily zero, making it perpendicular to the downward acceleration. Throughout the motion, the horizontal component of velocity does not change, but it does not affect the direction of acceleration. Therefore, there are no points along the path where the velocity and acceleration vectors are parallel.
clamchowder
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Homework Statement


If the object is not thrown straight up or down, is there any point along the path where the velocity and acceleration vectors are parallel to each other?



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The Attempt at a Solution



I know that velocity would be positive, but while moving upwards, wouldn't the acceleration be negative because the ball is slowing down (neg acc and positive v=slowing down)? And vice versa for going down. At the peak, velocity and acceleration would be perpendicular because there is no vertical velocity at that point, and acceleration would be facing downwards.
 
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Think: If the object is thrown at an angle it will have a horizontal velocity component and a vertical velocity component. The acceleration, as you said is always vertically downward. What do you know about the horizontal component of velocity?

ehild
 
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