Solving Physics Problems: Ball Drop and Race Calculations

AI Thread Summary
The discussion revolves around solving two physics problems involving motion. The first problem involves two individuals on an 80 m high roof, where one throws a ball upwards and the other drops a ball. Key calculations include determining the time difference in when they hit the ground, their final velocities, and the displacement between them. The second problem features a race between a rabbit and a tortoise, with the rabbit resting before starting and ultimately losing by 100 cm despite being significantly faster. Participants seek assistance with equations of motion, particularly related to free-falling objects and the time it takes for the ball thrown upwards to return to the roof level.
dmasports
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I've been having some problems with these problems, I'd appreciate any help.

1. There are 2 people standing on a roof 80 m high, person #1 throws a ball straight up in the air with an initial velocity of 20 m/s, person #2 has a replica of the ball and drops it off the roof at the same initial velocity.

How much sooner does #2 hit the ground than #1?

What is the difference in their final velocities?

What is the displacement between #1 and #2

2. There is a race between a rabit and tourtise, the rabit rests for 10 min before starting and is 50 times faster than the tourtise. The tourtis's speed is 5 cm/s, and it ends up loosing the race by 100 cm.

How longs the race?

How long does the race last?




Thanks for the Help! :cool:
 
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For the first one, what is the speed of ball #1 when it returns to the roof level on the way down?

How would you find the time it takes to reach its peak of motion and return to the roof level?

What do you know of the equations of motion of a free falling object?
 
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all that was given to us was that accleration is 9.81 m/s, besides that nothing else is known
 

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