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.
These bugs, known as sand fleas or jiggers, dig into your feet at the heel, sole, or toes. They cause a skin disease called tungiasis. You donât feel it when they go in. But they grow up to 2,000 times bigger once inside your foot. This makes your skin itchy and irritated. Your foot may also swell and get ulcers. Some people get gangrene or tetanus.