הצגת המקור של הדף "Static and dynamic load"

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'''[[עומס דינאמי ועומס סטאטי]]''' 

A '''dynamic load''' or '''shock load''' is an unconstant load, that can rapidly change in  time.

A '''static load''' is a constant load on a system or an anchor.

The differences between static and dynamoc loads can be easily demonstrated with a simple experiment:
# Gently and slowly place a load (a pack of sugar, for example) on a kitchen scale. What is the highest reading? What was the nature of the scale pointer movement? what was the reading a few seconds later?
# Drop  the same load onto the scale. What is the highest reading in this case? What was the nature of the scale pointer movement ? what was the reading a few seconds later?

In rope systems a true static load is rare, even though in most cases it is near static. Mopst people think that the load is dynamic only when breaking a [[leading|lead]] [[fall]]. Let us consider a few cases:
* While [[free climbing]], for most of the time, all parts of the belay system (anchors, [[ropes|rope/ropes]], [[harness|harnesses]], [[belay device]] etc.) are not loaded. In case of a fall there is a dynamic loading of the whole system.
* While [[aid climbing]], there is an almost static load on the leader's harness, on his/her [[cow's tail]] or [[daizy chain]] and on the last piece. Every time the leader pulls or steps up on an anchor, the load becomes more dynamic.
* While [[rappeling]], the rope, harness and ancors are constantly loaded. It seems like a static load, but the load changes with rappeling speed. In a very jerky rappel, where the person alternately free falls and then abruptly stops, the load changes radically; when falling, there is no load, when stopping, the load rises quickly, and is actually just like breaking a fall. Furthermore, bouncy rappels repeatedly puts a dynamic load on the anchors. It is especially important when using [[single point of failure|just one anchor]] with no back up. 
* When [[toprope|toproping]], there might also be a dynamic load. When the climber climbs, there is no loading, and when he falls, there is, i.e. the load changes. of coursae, the load in this case is not as high as in a lead fall. 
* A failure of a piece of protection within a [[complex anchors|complex anchor]] of a belay might, depending on system configuration, cause the remaining pieces to be shock loaded. This applies especially to a sliding x anchor, as it allows for a long extention. This is more serious in [[rope rescue]] systems with pulling systems where loads are high.  This is a major consideration on long [[trad]] routes and in the mountains, when marginal anchors are not rare. usually, it is preferable to use a [[cordelette]] rather than a sliding x.
==dynamic and static load in ropes==

==further reading==
* [[Dynamic belay]]

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