a double knot
That would depend on the wall thickness everything being equal cast is heavier
What measure of units would you use to measure the thickness of a phone book
Why would you want to add thickness?
ring ropes are vinyl covered elevator cables. you would be hard pressed to find anything comparable.
This is an old sailing term. If you knew your ropes, you knew which rope on a sailing ship would do which task, and you were a good and experienced sailor. Nowadays, you say that any experienced person "knows the ropes."
Untie it as you would any other knot.
An ultrasonic thickness gauge is required for measuring the thickness of different types of materials. The best ultrasonic thickness gauge you can buy is the Defelsko Corporation Ultrasonic Thickness gauge.
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This would be a line, which has no width, no thickness and no endpoints, but has infinite length.
First off, there are static and dynamic ropes. Static ropes do not stretch and are mostly used for rappelling, hauling, fixed lines, and probably some other stuff I do not know about. This is because none of these activities involve large forces - such as what would be created during a fall. Dynamic ropes stretch, and are the main type of rope used for rock climbing. This is because they stretch to absorb the shock of the climbing rope. In fact, if I remember correctly, some rock climbing ropes can stretch to as much as 30% more than it's original length. Dynamic ropes come in a wide range of diameters and can also be divided into three categories - single ropes, half ropes, and twin ropes. One would choose a certain diameter and type of rope based on the activity they plan on doing.
thickness
The thickness of the Earh's crust about 40 km will be at the contenintal crust.