Finding the Apex of a Thrown Ball: Does Mass Matter?

AI Thread Summary
To determine the apex of a thrown ball, mass is irrelevant as all objects experience the same gravitational acceleration. The initial speed of 22.2 m/s and the total time of 4.10 seconds can be used to calculate the time to reach the apex, which is half of the total flight time. At the apex, the velocity is zero, allowing for kinematic equations to be applied to find the height. Various methods exist to calculate the apex height once the time is established. Understanding these principles allows for accurate predictions of projectile motion.
jasonalan
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if a 2 kg ball is thrown upward at a speed of 22.2 m/s and it hits the ground after 4.10 s, can I use this information to find out when and where it is at the apex? Does the mass come into play, or is it the same for all objects?

Thanks.
 
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jasonalan said:
if a 2 kg ball is thrown upward at a speed of 22.2 m/s and it hits the ground after 4.10 s, can I use this information to find out when and where it is at the apex? Does the mass come into play, or is it the same for all objects?

Thanks.

Mass doesn't matter. It's the same for all objects. You can solve the problem purely kinematically, ie you don't use the mass at all.
 
Thanks, How would I do this?
 
jasonalan said:
Thanks, How would I do this?

You can find the time to reach the apex immediately. What do you know about the velocity at the apex?

Once you know the time to reach the apex, try to use that to find the height of the apex... there are a couple of different ways to do this.
 
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