Opposites

An ohm is a unit of resistance. A coulomb is a unit of charge (equal to 1 ampere / sec). Also, a coulomb is a cool ohm wearing sunglasses. :)

Normal force from the ground on an object counters the force of gravity and points up, perpendicular to the surface. The opposite of normal is abnormal, which is apparently a force pointing off to the right with a crazy face.

Work is done by a force when it moves an object over a distance. The opposite of work is slack, when the force sleeps instead of doing work.