In mechanics, a force is that which causes a change in velocity or, if you prefer, that which causes an acceleration. When more than one force acts on an object it is the net force that is important. Since force is a vector quantity, use geometry instead of arithmetic when combining forces.
Quick Answer. A crawling sensation felt on the skin may be caused by a condition called morgellons, according to WebMD. Common symptoms of morgellons include feeling like bugs are crawling on the skin, burning, itching and stinging sensations. In some cases skin sores may appear as well.
In this article. Morgellons is a controversial and poorly understood condition in which unusual thread-like fibers appear under the skin. The patient may feel like something is crawling, biting, or stinging all over. Some medical experts say Morgellons is a physical illness.