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.
Cellulitis Cellulitis, a bacterial infection of the skin, causes red, tender skin that is usually swollen and warm. Hidradenitis suppurativa Hidradenitis suppurativa is a condition of the sweat glands causing painful sores, pus, itching, and foul odor. Insect bites Redness, swelling, pain, itching, bumps are common symptoms of insect bites. Insect sting An insect sting may be followed by redness, swelling, and itching. Chemical burns A chemical burn can cause symptoms ranging from burning and blisters to pain and shortness of breath.