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.
Restless legs syndrome, also known as Willis-Ekbom disease, is a common condition of the nervous system that causes an overwhelming, irresistible urge to move the legs. It can also cause an unpleasant crawling or creeping sensation in the feet, calves and thighs. The sensation is often worse in the evening or at night.