Mike wrote:
> This may seem silly and probably is but I have no physics experience.
> If you put two anchors in and attached both of them to the same guy wire
> and there was 5000 pounds pull on it wouldn't both of them have 5000 pound
> pull on them???
> Isn't it kinda like putting resistors in parallel the same voltage would be
> present on both of them.
> This may seem stupid to most of you but like I said, no physics classes
> were offered at my school.
>
Mike,
It may help to think of one crane lifting one 5000 pound car. If the
crane lifts the car with just one wire rope, then that wire rope has
5000 pounds of tension on it. On the other hand, suppose the one
crane uses two wire ropes attached to the car. Since the car still weighs
only 5000 pounds, then each wire rope can be lifting only 2500 pounds if
the weight is evenly divided. Now suppose that a single wire rope comes
down from the crane to a point just ten feet over the car and from there two
ropes are used, one going ten feet forward to the front of the car and one
going ten feet backward to the back of the car.
In this case, the single wire rope has 5000 pounds of tension on it. What
may not be so obvious, however, is that the wire going to the front of the
car now has 1.414 times 2500 pounds or 3,535 pounds of tension on it,
and the back rope also has 3,535 pounds of tension on it. One side
effect is that the front bumper and the back bumper are being pulled
together by the two ropes as well as both being lifted upward by the two
ropes. This "pulling together" force can only come from the ropes, so it
has to appear on each rope as tension, added to the tension from the
weight of the car.
Hope that makes it clearer.
Lyn
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