1 Answer
A **DC voltmeter** is a type of instrument used to measure the **voltage** (potential difference) across two points in a **direct current (DC)** circuit. It tells you how much electrical pressure or potential difference exists between those points. DC voltage remains constant over time, unlike AC (alternating current) which varies in direction.
### Key points about DC voltmeters:
1. **Measuring DC Voltage:** It specifically measures **DC voltage**, which doesn’t change direction over time. If you try to measure AC voltage with a DC voltmeter, it won’t give accurate readings because it’s designed to measure a constant voltage.
2. **Display:** It usually shows the voltage value on a digital or analog display. The unit of measurement is **volts (V)**.
3. **Connection:** You connect the two probes of the voltmeter to the two points you want to measure. One probe goes to the positive side, and the other goes to the negative or ground side.
4. **Application:** It’s used in a wide range of applications, from testing batteries and power supplies to diagnosing faults in electronic circuits.
### How it works:
- Inside the voltmeter, there’s a **high internal resistance** which means it doesn’t draw significant current from the circuit. This ensures that it doesn't affect the circuit you're measuring.
- When you connect it across two points in a circuit, it measures the potential difference between those points without significantly altering the circuit's behavior.
So, in simple terms, a **DC voltmeter** is just a tool for checking how much electrical “push” is available at different points in a DC circuit.
### Key points about DC voltmeters:
1. **Measuring DC Voltage:** It specifically measures **DC voltage**, which doesn’t change direction over time. If you try to measure AC voltage with a DC voltmeter, it won’t give accurate readings because it’s designed to measure a constant voltage.
2. **Display:** It usually shows the voltage value on a digital or analog display. The unit of measurement is **volts (V)**.
3. **Connection:** You connect the two probes of the voltmeter to the two points you want to measure. One probe goes to the positive side, and the other goes to the negative or ground side.
4. **Application:** It’s used in a wide range of applications, from testing batteries and power supplies to diagnosing faults in electronic circuits.
### How it works:
- Inside the voltmeter, there’s a **high internal resistance** which means it doesn’t draw significant current from the circuit. This ensures that it doesn't affect the circuit you're measuring.
- When you connect it across two points in a circuit, it measures the potential difference between those points without significantly altering the circuit's behavior.
So, in simple terms, a **DC voltmeter** is just a tool for checking how much electrical “push” is available at different points in a DC circuit.