Question

define 1 columb., 1 ampere

Answer 1

The ampere (symbol: A), often shortened to "amp", is the base unit of electric current in the International System of Units (SI). ... The amperewas then defined as one coulomb of charge per second. In SI, the unit of charge, the coulomb, is defined as the charge carried by one ampere duringone second.A quantity of 1 C is equal to approximately 6.24 x 1018, or 6.24 quintillion. In terms of SI base units, the coulomb is the equivalent of oneampere-second. Conversely, an electric current of A represents 1 C of unit electric charge carriers flowing past a specific point in 1 s.

Answer 2

HI !

Current is the flow of electrons or charges.
Current is represented by "I"
The SI Unit of current is Ampere(A)
We have a formula to calculate the current passing through a conductor in unit time ,

I =  Q / t

where I = current
 Q = charges [ si unit = coulomb{C} ]
t = time [ si unit = seconds{sec}]

that is ,

1 A = 1 C/ 1 sec
       = 1 C s⁻¹

When 1 coulomb of charge , flows through a cross section of a conductor in t seconds , the current passing through the conductor is 1 ampere .

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One coulomb is the charge that flows through a conductor with a current of 1 ampere , in 1 sec.

Q = It

1 C = 1 A × 1 sec