Physics Question
 

Theoretical Situation: Two identical boats. One is towing the other with a
small diameter (undersized for the job) 30' rope.

Question: When the rope snaps, which way will it go?

Should it snap back towards the boat in tow (the load). Or should it snap
toward the boat pulling the load (the force)?

Physics Question
 

On 30 May 2004 17:39:14 GMT, obull (CCred68046)
wrote:

Theoretical Situation: Two identical boats. One is towing the other with a
small diameter (undersized for the job) 30' rope.

Question: When the rope snaps, which way will it go?

Should it snap back towards the boat in tow (the load). Or should it snap
toward the boat pulling the load (the force)?

Where did it snap? Whatever portion of the rope is still attached to
either boat will go toward that boat.

Steve

Physics Question
 

Some background before stating the answer:

The break will occur at the weakest point in the rope. This can be at any
location on the rope. This will leave two ends to be considered separately.
The primary motive force will be the initial elastic deformation of the
rope. At each rope segment contacts it will be drawn to the fixed attachment
point. The accelerating force may be in the magnitude of tons, and the mass
of the rope is likely to be very low in relation to this force. This
suggests that the rope may experience a large acceleration.

There are other forces involved. The inertia of the initial movement of the
rope will be dwarfed the movement induced by the initial tension on the
rope. As the rope contracts, any torsion induced by the lay of the rope will
tend to cause it to twist and coil. Any air movement, or relative air
movement because of boat motions, will further modify the movement of the
rope. Unless the boats are traveling very fast, or in a very high wind, the
initial contraction will be the largest force. As the rope decelerates due
to air friction, the relative air movement may become the final deciding
factor in how the rope moves. Or the stored energy in the flying rope end
may be transfer to any object that it runs into, such as the foolish captain
that tried to tow a boat with a rope that was clearly too small to do the
job.

The final answer:
The remainder of the rope on each end of the break will be drawn towards the
boat to which it is attached.

Mark Browne

"CCred68046" wrote in message
...
Theoretical Situation: Two identical boats. One is towing the other with
a
small diameter (undersized for the job) 30' rope.

Question: When the rope snaps, which way will it go?

Should it snap back towards the boat in tow (the load). Or should it snap
toward the boat pulling the load (the force)?

Physics Question
 

mark gives us gives us the Art History major version. If you are also an Art
History major, accept it. If not, ignore it. If you are a humorist, chuckle.

Some background before stating the answer:

The break will occur at the weakest point in the rope. This can be at any
location on the rope. This will leave two ends to be considered separately.
The primary motive force will be the initial elastic deformation of the
rope. At each rope segment contacts it will be drawn to the fixed attachment
point. The accelerating force may be in the magnitude of tons, and the mass
of the rope is likely to be very low in relation to this force. This
suggests that the rope may experience a large acceleration.

There are other forces involved. The inertia of the initial movement of the
rope will be dwarfed the movement induced by the initial tension on the
rope. As the rope contracts, any torsion induced by the lay of the rope will
tend to cause it to twist and coil. Any air movement, or relative air
movement because of boat motions, will further modify the movement of the
rope. Unless the boats are traveling very fast, or in a very high wind, the
initial contraction will be the largest force. As the rope decelerates due
to air friction, the relative air movement may become the final deciding
factor in how the rope moves. Or the stored energy in the flying rope end
may be transfer to any object that it runs into, such as the foolish captain
that tried to tow a boat with a rope that was clearly too small to do the
job.

The final answer:
The remainder of the rope on each end of the break will be drawn towards the
boat to which it is attached.

Mark Browne

"CCred68046" wrote in message
...
Theoretical Situation: Two identical boats. One is towing the other with
a
small diameter (undersized for the job) 30' rope.

Question: When the rope snaps, which way will it go?

Should it snap back towards the boat in tow (the load). Or should it snap
toward the boat pulling the load (the force)?

Physics Question
 

Both free ends will recoil, with the longest section of rope recoiling with
the greatest force.

"Steven Shelikoff" wrote in message
...
On 30 May 2004 17:39:14 GMT, obull (CCred68046)
wrote:

Theoretical Situation: Two identical boats. One is towing the other with
a
small diameter (undersized for the job) 30' rope.

Question: When the rope snaps, which way will it go?

Should it snap back towards the boat in tow (the load). Or should it
snap
toward the boat pulling the load (the force)?

Where did it snap? Whatever portion of the rope is still attached to
either boat will go toward that boat.

Steve

Physics Question
 

Jax,

How do broken ropes fly in JaxWorld?

Mark Browne

"JAXAshby" wrote in message
...
mark gives us gives us the Art History major version. If you are also an
Art
History major, accept it. If not, ignore it. If you are a humorist,
chuckle.

Some background before stating the answer:

The break will occur at the weakest point in the rope. This can be at any
location on the rope. This will leave two ends to be considered
separately.
The primary motive force will be the initial elastic deformation of the
rope. At each rope segment contacts it will be drawn to the fixed
attachment
point. The accelerating force may be in the magnitude of tons, and the
mass
of the rope is likely to be very low in relation to this force. This
suggests that the rope may experience a large acceleration.

There are other forces involved. The inertia of the initial movement of
the
rope will be dwarfed the movement induced by the initial tension on the
rope. As the rope contracts, any torsion induced by the lay of the rope
will
tend to cause it to twist and coil. Any air movement, or relative air
movement because of boat motions, will further modify the movement of the
rope. Unless the boats are traveling very fast, or in a very high wind,
the
initial contraction will be the largest force. As the rope decelerates
due
to air friction, the relative air movement may become the final deciding
factor in how the rope moves. Or the stored energy in the flying rope end
may be transfer to any object that it runs into, such as the foolish
captain
that tried to tow a boat with a rope that was clearly too small to do the
job.

The final answer:
The remainder of the rope on each end of the break will be drawn towards
the
boat to which it is attached.

Mark Browne

"CCred68046" wrote in message
...
Theoretical Situation: Two identical boats. One is towing the other
with
a
small diameter (undersized for the job) 30' rope.

Question: When the rope snaps, which way will it go?

Should it snap back towards the boat in tow (the load). Or should it
snap
toward the boat pulling the load (the force)?

Physics Question
 

Jax,

How do broken ropes fly in JaxWorld?

Mark Browne

"for each force there is an equal and opposite force"

Physics Question
 

Also Sprach JAXAshby :
mark gives us gives us the Art History major version. If you are also an Art
History major, accept it. If not, ignore it. If you are a humorist, chuckle.

And Jax gives us the Asshat version. If you are an Asshat, accept it. If
not, ignore it.

Dan

--
So Pikachu walks around muttering "Pikachu! Pikachu! Pikachu!"
like a sad, deranged grandfather high on helium.

-- The Self Made Critic

Physics Question
 

On Sun, 30 May 2004 20:40:06 GMT, "Mark Browne"
wrote:

How do broken ropes fly in JaxWorld?

===================================

All things fly very high in JaxWorld.

The fuel is unknown but we could make some educated guesses.

Physics Question
 

"JAXAshby" wrote in message
...
Jax,

How do broken ropes fly in JaxWorld?

Mark Browne

"for each force there is an equal and opposite force"

Jax,

You have demonstrated that the scientists on JaxWorld have heard statements
relating to Static's, but they are still struggling to learn what they mean.
Have the researchers on JaxWorld heard about the branch of mechanical
engineering known as Dynamics? If it would be helpful I can point you to
some nice engineering texts that might help you understand these strange new
concepts.

Until then, I can help you understand a little bit about these strange new
ideas.

In a state of STATIC balance, your statement would be true.
Just before the rope parted the entire towing force was transferred through
the rope. The rope obeys hooke's law, where the stress of the towing effort
results in strain in the rope. The rope strains in elastic deformation. I
know that this might be a little tough for you to follow, but in this
situation, the rope is a spring.

Our friends at google can help you learn about this Hooke's law thing:
http://www.google.com/search?hl=en&i...7s+law&spell=1
Any one of the first ten links should do the job.

As the rope parts the static's view is no longer valid; we enter the new
land of ACCELERATION and MOTION.
The energy stored in the rope (as elastic deformation) is released when the
rope parts. This stored energy acts to accelerate the rope. The force stored
in the rope acts against the fixed support to accelerate the rope.
(Considering the relative mass of the boat and the rope, we can safely
ignore the effect on the boats for this discussion) The rope reaches is
maximum speed when the stored energy is fully converted to motion.

Back to your original message quoted above, you should have paid a little
more attention to your high school physics class.
I belive that the statement you where groping for was Newton's third law :

"For every action, there is an equal and opposite reaction."

In subtle but important ways, this is different from the rule you offered.
If you wish learn more about the issue, this little primer may do the trick:
http://www.glenbrook.k12.il.us/gbssc...aws/u2l4a.html

Have a nice day,

Mark Browne