In article ,
Harry K wrote:
(John Cochran) wrote in message ...

SNIP

No it isn't. If you tie the other end of the rope to the load instead
of the anchor, this is what you get.


|
|
O
| |
| |
| |
This half ----- | | --- This half of the rope has 20 lbs of tension.
of the rope | |
has 20lbs of | |
tension | |
| |
+---+-+--+
| 40 lbs |
+--------+


For the situition that you have


|
|
O\
| \
| \
This half ------ | \ --- This half of the rope has 40 lbs of tension
of the rope has | \
40 lbs of | \
tension | \
| \
| . Anchor
+----+---+
| 40 lbs |
+--------+

No matter how you do it, in order to support the 40lb load, the sum of
all ropes attached to the load has to add up to 40lbs. If you're using
a simple pulley at the top and attach both ends of the rope to the load,
then the rope has a tension of 20lbs and both sides add up to a total
of 40 lbs. If you instead attach one end of the rope to an anchor, then
the rope has an tension of 40 lbs and the hook at the top is having to
support a total of 80 lbs.

The weight will remain quite nicely right where it is.
What is the pull on the hook?? Where did the 40 lbs go??

I hope you answer this as you do appear to know what you are talking
about. Just don't let what seems logical lead you down stray paths.
Yes, on first glance the original problem appears to need a 80 lb
strain but unfortunately it isn't true in real life. A simple test (or
reference to any physics text) will show you in less than a minute.

Harry K

You didn't show how attaching the rope back to bucket is in anyway
different than attaching to a separate anchor. You are still assuming
a non-existant 40 lb load. It is the same load extended to the anchor
or the bucket handle. The text book I did find did at least -mention-
the force extending through the hook but did not specifically mention
what the force was, i.e., was it 1/2 the load or the whole load.

Harry,
LOOK at the 1st diagram on this posting. The one that shows both ends
of the rope attached to the 40lb load. You'll notice that both ends have
20lbs of tension. Two rope ends at 20lbs each is capable of supporting
a 40lb load.

Now LOOK at the 2nd diagram where one end of the rope is attached to the
load and the other end is attached to an anchor. Now since there is only
one end of the rope attached to the load, that end has to have 40 lbs of
tension in order to support a 40 lb load. The other end of the rope also
has to have 40 lbs of tension in order to keep it from running out of
the pulley.

Now LOOK at the 1st diagram again. Note that the rope is under 20 lbs of
tension. Notice that the rope goes to and from the pulley for 2 force
vectors from the pulley. Each vector has 20 lbs and 2 times 20 is 40.

Once again LOOK at the 2nd diagram. Note that in this diagram the rope is
under 40 lbs of tension. Once again, notice that the rope goes to and from
the pulley for once again 2 force vectors. However, since the force vectors
are now 40lbs instead of 20lbs, the force that the top pulley is having to
support is now 40 times 2 for a total of 80 lbs.

The tension in the rope doubles when going from both attachment points on
the load to a single attachment point on the load and a single attachment
point on an anchor.

Personally, I enjoy teaching someone something and seeing the light bulb
go off when the student realizes what is going on. But, I'll forgo that
pleasure in your case since it seems that the bulb is burnt out.

If you continue to ignore what everyone else in this newsgroup continues to
say, then I can only come to one of three conclusions.

1. You're a idiot.
2. You're a liar.
3. You're a troll.

I really don't care which of the above conclusions is the correct one since
it's obvious that in all three cases the correct thing to do is to drop it
and allow you to kill yourself off (hopefully before you reproduce) by
killing yourself in the future by overloading a hoist due to your massive
ignorance of physics.

Later people.

DON'T FEED THE TROLL