PHYSICAL QUANTITY

Electric current: formulas and units of measurement

Electric current: symbol I, unit A. Formulas and explanations for Electricity.

Iampere

KEY CONNECTIONS

Formulas

I = q / t

I = U / R

I = ε / (R + r)

I = qnvS

j = I / S

m = kelIt

NOTATION

: Current strength is the charge passing through the cross section of a conductor per unit time.
: Electric charge is a quantity that determines the participation of a body in electrical interaction.
: Time is a quantity characterizing the duration and sequence of events.
: Electric voltage is the work done by the electric field when transferring a unit charge.
: Electrical resistance is a measure of a conductor's resistance to electric current.
: Electromotive force is the work of external forces during the transfer of a unit charge.
: Internal resistance is the resistance of the electric current source.
: Concentration is the number of particles per unit volume.
: Speed is the speed and direction of change in body position.
: Area is the size of a surface or cross section.
: Current density is the current strength per unit cross-sectional area.
: Mass is a scalar physical quantity that is a measure of the inertia of a body.
: Electrochemical equivalent is the mass of a substance released by a unit charge.

THEORY

PRACTICE

Topics in order: the concepts, quantities and formulas of a lesson with explanations and examples.

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