Answer / pankaj semwal

A.c. is scalar quantity,but at a given frequency it is specified by its amplitude and phase angle,since the amplitude may be considered as the magnitude and the phase angle as the direction of a vector.to account this difference the term phasor has been adopted instead of term vector.

Answer / nagaraju.g

vector

Answer / mohamed ghanem

vector which we expressed it by magnitude and phase angle and its angle means the time delay that current come or affect after the voltage applied.

Answer / 7anoter4

I forgot to mention that a vector field produces a "flux"
an integration of the vectors in a limited cross section
area and this result it is a scalar, indeed. This is the
case of magnetic flux[F-Wb] as an integration of magnetic
flux density[B-Wb/m^2].In this case you may consider the
current as integration of current density field in a
conductor cross section area. Then the "current" is
physically a "scalar" but ac current can be represented on
a paper as "phase-vector" as explained.

Answer / guest

vector

Answer / 7anoter4

In my opinion, if someone is speaking about "vector"
and "scalar" in the same time he is referring to the
physical definition and not to mathematical-symbolic one.

If "current" is a vector what could be "scalar" in symbolic
[complex number] definition?.

Answer / nikhil bhardwaj

absolutely yes, because by the basic definition of vectors we know vector has both the magnitude and direction thereby current is vector for ac as sinusoidal component consists of both magnitude and its phase angle i.e direction.

Answer / 7anoter4

Vector is a physical notion which means

a quantity that are fully described by both a magnitude and
a direction. Speed, force, electric field intensity,
magnetic field intensity, current density and other are
vector defined by a magnitude and a direction.

With a field of quantities define as vectors you may use
function like gradient, curl and divergence and product as
vectorial or scalar.

Scalar it is a quantity defined complete by the magnitude
as current intensity, magnetic flux ,electrical potential
and other.

In electrical calculation- in alternative current system-
it is employed a quantity defined as phasor or phasor-
vector formed of two parts: one real and one imaginary
quantity.

For instance, the real part of a current could be I*cos(fi)
where fi it is the angle between supplied voltage
[considered as fi=0] and I it is the measured current
[intensity].An imaginary part is annexed in order to
complete the image I*sin(fi).

Then we have three possibilities: only real part-
considering fi=0, only imaginary part considering fi=90
degree or a complex number I*cos(fi)+I*sin(fi)*i i=sqrt(-
1) an imaginary unit.

So, the ac current[intensity] is not a vector and not a
scalar but could be a complex number or a real quantity-
depends on how you'll take the "fi".

Answer / shuvadeep chatterjee

refering to my question....
where I am getting stuck is....AC cant be Scalar because in
Circuit Theory we show the direction of AC Current from
where it is flowing.And if it is Vector it breaks vector
laws since in a simple DC generator we actually generate AC
which we convert to DC using carbon brush.DC being scalar,
AC is breaking vector laws which states a vector quantity
having a specific direction cant be converted to scalar.

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