A weight of 15 lbs at sea level is suspended

In summary, the peak tension load on the wire will depend on the abruptness of the weight's stopping, which cannot be precisely determined in this scenario. The weight must also stretch slightly, making it impossible to determine an exact answer. However, a rough estimate within plus or minus 5 lbs can be made with the given information.
  • #1
Nornh
Yes, this is in regards to my first question.

A weight of 15 lbs at sea level is suspended by a wire rope that does not stretch. The weight is lifted 1 ft and dropped 1 ft. the initial velocity is "zero". What is the peak lb load on the wire when the weight stops falling?

Thanks for your reply.

This problem does not require a precise answer. I am looking for a plus or minus 5 lb answer. The missing factors that you have mentioned can be assumed in generalities. Is this enough information to come up with an answer?
 
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  • #2
the peak tension will depend very much on how abruptly the
weight is assumed to stop falling.

in a normal problem this would be influenced by the stretch
of the cable----the less elastic the cable the more abruptly
the object halts and the greater the force.

but your problem is not a problem in physics
since the cable does not stretch, and also it is not well posed since (unless information can
move faster than light) there is no "when"

there is no well-defined instant in time "when the weight'
stops falling"

To see this, imagine that the cable is attached at the top of
the weight. the weight must occupy a physical volume, must
have for example a height, say like 4 inches, between
the bottom and the top where the cable is attached.

when the cable snaps taut it stops the top of the weight
from falling, but the rest of the weight does not know about this
yet and keeps on falling.

so the weight itself must stretch slightly (unless information travels thru the weight at infinite speed)

so the deceleration of the weight is not instantaneous

if any deceleration is instantaneous one can say that the force applied is infinite---but that is not a physical process

so the deceleration of the weight is GRADUAL according to some timetable. If you would somehow indicate the timetable for the weight to stop falling and it would be possible to estimate the peak tension "load" as you ask
 

1. What is the weight of an object?

The weight of an object is a measure of the force of gravity acting on it. It is typically measured in pounds (lbs) or kilograms (kg).

2. How is weight affected by elevation?

As elevation increases, the weight of an object decreases. This is because the force of gravity is weaker at higher elevations due to the greater distance from the center of the Earth.

3. What is the weight of a 15 lb object at sea level?

A 15 lb object at sea level will have a weight of 15 lbs.

4. What does it mean for an object to be suspended?

An object is suspended when it is held in place without touching the ground or any other surface. This can be achieved through the use of ropes, strings, or other support structures.

5. Why is it important to specify "sea level" when discussing weight?

It is important to specify "sea level" when discussing weight because the force of gravity varies slightly at different elevations. This allows for more accurate and standardized measurements and comparisons of weight.

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