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#1 2011-07-11 15:55:43

AuraLucario
New Scratcher
Registered: 2011-05-03
Posts: 5

Ball

How do you make a ball look as if it is bouncing on the spot? It is for a bouncy ball project.

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#2 2011-07-11 17:45:17

GalionLibrary
New Scratcher
Registered: 2011-07-08
Posts: 9

Re: Ball

Umm, I'm not entirely sure what you mean by "on the spot", but I'm guessing you might want to start with moving the ball vertically but not horizontally.

Beyond that, if it's a school assignment, you'll probably want to assume that the ball is a point mass in a frictionless environment, that 100% of its kinetic energy is preserved when it bounces (so that it keeps bouncing indefinitely), and that gravitational force is precisely uniform across the entire region.  Just hold acceleration constant and multiply velocity by -1 whenever it hits the floor.

In a more realistic simulation, of course, it would land on the floor after a small number of bounces, due to various losses and inefficiencies, but your teacher almost certainly does not expect a realistic simulation.

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#3 2011-07-11 22:36:35

EdnaC
Scratcher
Registered: 2007-08-28
Posts: 100+

Re: Ball

Here's a simple demo of implementing Gravity that you can use to get started.  There are several others of varying complexity.  Feel free to remix as desired or just study the concepts.

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#4 2011-07-12 13:54:02

AuraLucario
New Scratcher
Registered: 2011-05-03
Posts: 5

Re: Ball

Thanks for all from both of you the help I got an ICT award for the bouncing

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