Ping Pong

[iago]

Nancy claims that she can throw a ping-pong ball so that it would go a short distance, come to a  dead stop, then reverse itself and come back.  She also added that she wouldn't bounce the ball off anything or tie anything to it.  How is this possible?

[Ergot]

vacuum ? throw it up?

[Newby]

Throw it up a hill? :p

[Sidoh]

She throws it straight up?

Things thrown up follow a parabolic path in space-time (which do come to a complete stop a the vertex of the parabola) due to the force of gravity.

[Quik]

Palm the ball, then throw it while tilting your hand at a 45° angle, allowing the ball to slide off the tip of your fingers before force is applied. The ball will come to a stop when it hits the ground, then roll backwards because of backspin.

[Sidoh]

Palm the ball, then throw it while tilting your hand at a 45° angle, allowing the ball to slide off the tip of your fingers before force is applied. The ball will come to a stop when it hits the ground, then roll backwards because of backspin.

Occam's Razor. I win.

[Blaze]

Roll it with a backwards spin.

[Sidoh]

Roll it with a backwards spin.

I don't see anywhere in the riddle where it says it has to be a horrizontal throw.  Besides, rolling isn't throwing.

[Blaze]

Roll it with a backwards spin.

I don't see anywhere in the riddle where it says it has to be a horrizontal throw.  Besides, rolling isn't throwing.

I ment throw it with a backwards spin.

[Sidoh]

I ment throw it with a backwards spin.

Once again, I win (theoretically) due to Occam's Razor. 

[iago]

I ment throw it with a backwards spin.

Once again, I win (theoretically) due to Occam's Razor. 

Yes, you are correct.  Occam's Razor is indeed appropriate here. 

We had a poster at work about Occam's Razor I should have taken a picture of. It is so important in security

Technically, Ergot was right first. 

[Sidoh]

Technically, Ergot was right first. 

He edited it before I posted, I swear.  His original post only contained "vacuum."

Haha, at least I'm pretty sure. 

[iago]

Technically, Ergot was right first. 

He edited it before I posted, I swear.  His original post only contained "vacuum."

Haha, at least I'm pretty sure. 

It doesn't say "edited by..."

But if you thought of it independently, then you can still feel good about yourself.  Even if you ARE a dirty cheater..

[Blaze]

He edited it before I posted, I swear.  His original post only contained "vacuum."

Its still a good twenty minutes before you posted.

[Sidoh]

It doesn't say "edited by..."

But if you thought of it independently, then you can still feel good about yourself.  Even if you ARE a dirty cheater..

Hehe, I did.

If you edit your own post within the next minute or so after you post something, the "edit" tag doesn't appear.

Its still a good twenty minutes before you posted.

I still thought of it on my own.  I didn't take the time to read his stupid three word post!

Honestly, I didn't read his post.  I think I remember reading "vacuum" and kind of laughing because it made no sense, but I thought of my answer almost instantly after I read the question.

I also provided reason for why it was the way it was

AAANND I pwned you with Occam's Razor.