Ef

Effective Address

The final memory address used by an instruction.

Effective Nuclear Charge

The nuclear charge experienced by an electron when other electrons are shielding the nucleus.

Effective Perceived Noise Level

There are a number of different noise criteria measurements used by local authorities to determine noise levels in the community.

Efficiency

A measure of how well a machine changes energy into useful energy.

Efflorescent

Efflorescent substances lose water of crystallization to the air.

Effusion

Movement of gas molecules through a small opening.