tra-, tract-, trac-, -tractive, -traction, -tracting, treat-, trai-
(Latin: drag, draw together; a drawing out or pulling)
2. Someone who agrees to furnish materials or to perform services at a specified price; especially, for construction work.
3. Something that contracts; especially, a muscle in the body.
- Like charges repel each other and unlike charges attract each other.
- The attraction or repulsion acts along the line between the two charges.
- The size of the force varies inversely as the square of the distance between the two charges.
- The size of the force is proportional to the value of each charge.
If the bodies are oppositely charged, one positive and one negative, they are attracted toward one another; if the bodies are similarly charged, both positive or both negative, the force between them is repulsive.
Coulomb's law applies only when the charged bodies are much smaller than the distance separating them and therefore can be treated approximately as point charges.
It is accomplished with an instrument (cryoprobe) whose extremely cold tip forms an adhesion (iceball) with the lens, thus permitting removal of the lens.