A physics puzzle
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- cheese lizard
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A physics puzzle
The scene: A truck, carrying a canon, pointing out the back, loaded with a soccer ball.
The speed of the soccer ball shot from the canon is 50Mph.
As the canon is being shot, the truck travels at 50Mph.
Question: What happens to the Ball ?
(Please use the spoiler tag for your answers!)
The speed of the soccer ball shot from the canon is 50Mph.
As the canon is being shot, the truck travels at 50Mph.
Question: What happens to the Ball ?
(Please use the spoiler tag for your answers!)
Cheers, Claude.
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- Administrator
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Re: A physics puzzle
I assume that
Spoiler
The ball travels away from the truck at 50MPH, remaining stationary relative to the ground. BUT this would just be for the split second after the cannon fires
StuartR
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- BronzeLounger
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Re: A physics puzzle
Spoiler
It could end up travelling at 100 mph, if the truck was travelling in reverse at the time!
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Re: A physics puzzle
Spoiler
The cannon ball will fall straight down (more or less) - see If You Are Moving at the Speed of a Bullet and Shoot Backwards, What Happens? for a video that demonstrates this.
Best wishes,
Hans
Hans
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- gamma jay
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Re: A physics puzzle
Spoiler
That was my "logical" guess; but thanks for the video proof Hans (and Mythbusters!)
Regards,
Rudi
If your absence does not affect them, your presence didn't matter.
Rudi
If your absence does not affect them, your presence didn't matter.
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- PlutoniumLounger
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Re: A physics puzzle
HansV wrote:Spoiler
The cannon ball will fall straight down (more or less) - see If You Are Moving at the Speed of a Bullet and Shoot Backwards, What Happens? for a video that demonstrates this.
Spoiler
But not if the cannon-ball was composed of photons!
Cheers
Chris
He who plants a seed, plants life.
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- cheese lizard
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Re: A physics puzzle
I think you've been PhotonShopping too muchChrisGreaves wrote:But not if the cannon-ball was composed of photons!
Cheers, Claude.
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- PlutoniumLounger
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Re: A physics puzzle
Funny you should mention that ....HansV wrote:A soccer ball composed of photons?
Many tears[sic] ago I read a book on Physics in which the author likened a search for particles as being rather like watching a soccer game in which the ball was invisible.
Of course, the players appear to be wandering around the field aimlessly for twenty minutes, occasionally falling to the ground and clutching a knee, shin, foot, or head.
Mystified, our observer finally notices that just before half the players raise their arms and cheer, a bulge appears for a second or two in the back of the net ...
Speaking of which:
Cheers
Chris
He who plants a seed, plants life.
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- PlutoniumLounger
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Re: A physics puzzle
Claude, you are, as usual, absolutely correct.Claude wrote:I think you've been PhotonShopping too much
Just yesterday I came across this in a book:- The little essay is the one about tea leaves, why they congregate in the centre of the base of a mug.
The book:- Cheers and Swerves
Chris
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He who plants a seed, plants life.
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- cheese lizard
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Re: A physics puzzle
No need for that part of your statement Stuart.StuartR wrote:BUT this would just be for the split second after the cannon fires[
Anyway, I just thought I'd use a 'puzzle' to bring this (un)expected fact to attention of loungers.
Cheers, Claude.
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- BronzeLounger
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Re: A physics puzzle
Closely related to the aspect of this I presume you were trying to point out Claude, is the Bullet Fired vs Bullet Dropped demonstration.
Alan
Alan
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- BronzeLounger
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Re: A physics puzzle
Neutrinos would work too ... and be just as likely as a soccer ball made of photons!HansV wrote:A soccer ball composed of photons?
Alan
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Re: A physics puzzle
I didn't want to discuss the issues of continued acceleration from the expanding air still leaving the cannon, and wind resistance.Claude wrote:No need for that part of your statement Stuart.StuartR wrote:BUT this would just be for the split second after the cannon fires[
StuartR
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Re: A physics puzzle
Wise decision too!StuartR wrote:I didn't want to discuss the issues of continued acceleration from the expanding air still leaving the cannon, and wind resistance.
Transitional ballistics is the least well understood of the ballistic regimes, but the best for sales of headache tablets to those unfortunate enough to have to work in it.
Edit: But on that topic, I just stumbled on the best video I've seen of the phenomena involved - even captures the "shock diamonds" in the aftermath.
Alan