Electric Current

Overview

Electric current is the flow of electric charge through a conductor, typically measured in amperes (A). It occurs when there is a net movement of charged particles, such as electrons, across a cross-section of the conductor over a specific period. The current can be direct (DC), where the flow of charge is in one direction, or alternating (AC), where the flow periodically reverses direction. The establishment of electric current is driven by a potential difference (voltage) across the conductor, which causes the charges to move. Understanding electric current is fundamental to the study of electricity and its applications in various devices and systems

Questions and Answers

  1. What is electric current?

    Electric current is the flow of electric charge through a conductor, typically measured in amperes (A).

  2. What are the two main types of electric current?

    he two main types of electric current are direct current (DC), where the flow of charge is in one direction, and alternating current (AC), where the flow periodically reverses direction.

  3. What causes electric current to flow in a circuit?

    Electric current flows in a circuit due to a potential difference (voltage) across the conductor, which creates an electric field that drives the movement of charge carriers.

  4. What is meant by "drift velocity" in the context of electric current?

    Drift velocity refers to the average velocity that charge carriers, such as electrons, acquire due to an electric field, resulting in a net flow of current.

  5. What happens to the current in a circuit if the resistance increases while the voltage remains constant?

    If the resistance increases while the voltage remains constant, the current will decrease, as described by Ohm's Law.

Multiple-Choice Questions

  1. What is the SI unit of electric current?

    a) Volt
    b) Ohm
    c) Ampere
    d) Coulomb
    Answer: c) Ampere

  2. Which of the following best describes direct current (DC)?

    a) Current that changes direction periodically
    b) Current that flows in one direction only
    c) Current that has no flow
    d) Current that is only found in batteries
    Answer: b) Current that flows in one direction only

  3. In a metallic conductor, what are the primary charge carriers?

    a) Protons
    b) Neutrons
    c) Electrons
    d) Ions
    Answer: c) Electrons

  4. According to Ohm's Law, what happens to the current if the voltage is increased while resistance remains constant?

    a) The current decreases
    b) The current remains the same
    c) The current increases
    d) The current becomes zero
    Answer: c) The current increases

  5. What is the term used to describe the average velocity of charge carriers in a conductor due to an electric field?

    a) Drift velocity
    b) Thermal velocity
    c) Random velocity
    d) Instantaneous velocity
    Answer: a) Drift velocity