Understand Why Current Is Defined as a Scalar

In summary, current is the rate of flow of electric charge in a circuit, measured in amperes (A). It is defined as a scalar quantity because it only has magnitude and does not have a specific direction. It is different from voltage and resistance, as they are related through Ohm's Law. Current can be negative, indicating the flow of charge in the opposite direction or the presence of negatively charged particles. It is measured using an ammeter, which measures the amount of charge passing through a specific point in the circuit per unit time.
  • #1
hasan_researc
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0

Homework Statement



Why has current been defined to be a scalar?


Homework Equations





The Attempt at a Solution



No idea whatsoever!
 
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  • #2
Current density , as you know, is a vector. Current flowing across a fixed piece of surface is the integral of the current density over the surface(=(int)J.dA). Thus,the current is a scalar (but may depend on time).
 
  • #3
Because it is defined as the number of charges moving through the cross-sectional area of the wire per time unit.
 

1. What is the definition of current?

Current is the rate of flow of electric charge in a circuit, measured in amperes (A).

2. Why is current defined as a scalar quantity?

Current is defined as a scalar because it only has magnitude and does not have a specific direction. It is simply a measure of the amount of charge flowing in a circuit.

3. How is current different from voltage and resistance?

Voltage is the driving force that pushes electric charges through a circuit, while resistance is the measure of the opposition to the flow of current. Current, on the other hand, is the actual flow of charge in the circuit. They are all related through Ohm's Law: V=IR.

4. Can current be negative?

Yes, current can be negative. This indicates that the flow of charge is in the opposite direction, or that the charge carriers are negatively charged particles, such as electrons.

5. How is current measured?

Current is measured using an ammeter, which is connected in series with the circuit. The ammeter measures the amount of charge passing through a specific point in the circuit per unit time and displays it in amperes (A).

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