Electric Circuits and Ohm's Law: Understanding the Basics

Understanding Electric Current and Circuits

Electric current is the passage of electrical charge through a conductor. This occurs when there is an imbalance of charge between two points of the conductor.

An electric circuit is a set of elements connected together through which electric current flows. For current to flow, the circuit must be closed.

Components of an Electric Circuit

• Generator: Builds and maintains the voltage needed to produce the current.
• Conductors: Pathways through which the electric current flows, usually made of copper or aluminum.
• Receivers: Elements that transform electrical energy into other forms of energy.
• Switching and Control Elements: Direct the flow of electrical current.
• Protection Elements: Protect individuals and the circuit from potential overloads that can occur unexpectedly.

Types of Circuit Connections

• Series Connections: Elements are placed one after another, connected by lead wires. The current must pass through each element sequentially. If any element is disconnected, the entire circuit is switched off.
• Parallel Connections: All elements are connected to the positive and negative terminals of the generator. The electrical voltage is the same for all elements in the circuit. When elements are combined, the two types of circuits form a mixed circuit.

Circuit Control Elements

• Buttons:
  • Normally Open: Only allow current to pass when pressed.
  • Normally Closed: Stop the current flow until pressed.
• Circuit Breaker: An electrical component designed to permanently open or close a circuit when pressed again.
• Crossover Switch: A four-contact switch where contacts are connected two by two. When pressed, it crosses the connections.

Ohm's Law

Ohm's Law states that the voltage applied at the ends of an element equals the current flow multiplied by the resistance of that element to the flow of electric current. Mathematically, it is represented as: V = R x I.

• Voltage: Indicates the amount of energy a generator can provide to each load. It is measured in Volts.
• Intensity: Indicates the amount of charge passing through a section of the conductor in a given time. It is measured in Amperes.
• Electrical Resistance: Indicates the opposition a conductor presents to the flow of current. It is measured in Ohms.