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Calculation of voltage

Description

Calculate voltage in DC and AC circuits using key electrical parameters.

"Difference in electric potential between two points."

Key Parameters

Current Type

Direct Current (DC): Current flows constantly from positive to negative pole. Used in batteries, solar panels, and electronics.

Alternating Current (AC): Current reverses direction and amplitude over time at a constant frequency (e.g., 50 Hz or 60 Hz). Used in power grids and homes.

System Types:

  • Single-phase: One phase conductor and one neutral.
  • Two-phase: Two phase conductors (rare).
  • Three-phase: Three phase conductors; four-wire includes neutral.

Current (I)

Flow of electric charge through a material, measured in amperes (A).

In AC circuits, current may have a phase shift relative to voltage.

Active Power (P)

Real power that is actually consumed by a load, measured in watts (W).

Formula: P = V × I × cosφ

Example: A heater converts active power into heat.

Reactive Power (Q)

Power that alternately flows in reactance without being transformed into other forms of energy, measured in VAR.

Formula: Q = V × I × sinφ

Apparent Power (S)

Total power flowing in the circuit, combining active and reactive components, measured in VA.

Formula: S = V × I

Relationship: S² = P² + Q²

Power Factor (PF)

Ratio of active power to apparent power: PF = cosφ, where φ is the phase angle between voltage and current.

Resistance (R)

Tendency of a body to oppose the passage of electric current, measured in ohms (Ω).

Applies to DC circuits and AC resistive loads.

Ohm’s Law: V = I × R

Impedance (Z)

Opposition of a circuit to alternating current, measured in ohms (Ω).

Includes resistance and reactance: Z = √(R² + X²)

In AC circuits: V = I × Z

Key Formulas (Pure HTML)

V = I × R
V = P / I
V = √(P × R)
V = I × Z

Application Scenarios

  • Designing power supplies and converters
  • Troubleshooting voltage drops in wiring
  • Calculating transformer ratings
  • Improving power factor in industrial plants
  • Analyzing efficiency of electrical systems
  • Educational tools for physics and engineering students

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