1. What is Terminal Voltage?

Definition: Terminal voltage is the potential difference across the terminals of a power source when current is flowing.

Purpose: It helps determine the actual voltage available to a circuit, accounting for internal losses in the power source.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( V_t \) — Terminal voltage (Volts, V)
• \( E \) — EMF (Volts, V)
• \( I \) — Current (Amperes, A)
• \( R \) — Internal resistance (Ohms, Ω)

Explanation: The EMF is reduced by the voltage drop across the internal resistance (I×R) to give the actual terminal voltage.

3. Importance of Terminal Voltage Calculation

Details: Understanding terminal voltage is crucial for designing circuits, selecting power sources, and troubleshooting voltage drops.

4. Using the Calculator

Tips: Enter the EMF of your power source, the current flowing in the circuit, and the internal resistance of the power source.

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between EMF and terminal voltage?
A: EMF is the theoretical maximum voltage, while terminal voltage is the actual voltage under load.

Q2: When would terminal voltage equal EMF?
A: When no current is flowing (open circuit) or when internal resistance is zero.

Q3: How do I find internal resistance?
A: Measure voltage under load and no-load conditions, then calculate using R = (EMF - V_t)/I.

Q4: Can terminal voltage be higher than EMF?
A: Normally no, unless dealing with special cases like charging batteries.

Q5: Why does terminal voltage decrease with current?
A: Because the voltage drop across internal resistance (I×R) increases with current.