How Fast Was the Ball Thrown in This Projectile Motion Problem?

AI Thread Summary
The problem involves calculating the initial velocity of a ball thrown at a 30-degree angle, landing on a building 20 meters away and 5 meters higher than the starting point. The solution indicates that the initial speed is 20 m/s. Participants discuss the need to separate the motion into horizontal and vertical components to solve the problem effectively. They suggest using kinematic equations, particularly rearranging v² = u² + 2as, to find the initial velocity. Understanding the angle of projection is crucial for accurate calculations in projectile motion.
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A ball is thrown upward at an angle 30 degrees above the horizontal and lands on the top edge of a building 20 m away. The top edge is 5m above the throwing point. How fast was the ball thrown?

ANS 20 m/s.

I just can't seem to get this. It looks like there is a piece of info missing but I know that's not the case. Any hints?
 
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there are enough values to solve this problem
you need to calculate horizontal component and vertical component
 
have you tried using v2= u2+2as ? I think rearranging that for u should work.
 
you've got to compute horizontal and vertical component because the ball was not thrown directly upward.. it was thrown at 30 degrees
 

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