V = IR
Where:
- V = Voltage in volts
- I = Current in amperes
- R = Resistance in ohms
Different Definition of Voltage
| Definition | Formula | Unit |
|---|---|---|
| The potential difference between two points in an electric circuit that imparts one joule of energy per coulomb of charge is called voltage | V=ΔU/Q | Volt (Joule/Coulomb) |
| Voltage is defined as electric potential along a wire when an electric current of one ampere dissipates one watt of power | V=PI | Volt (Watt/Ampere) |
| Voltage is defined as amperes times ohms | V=IR | Volt (Ampere – Ohm) |
| Voltage is standard unit of measurement used for voltage | 1 V = 1 kg m² s⁻³ A⁻¹ | Volt (SI base units) |
Daily Life Examples of Voltage
- Battery-Powered Devices: Smartphones operate at around 3.7 to 4.2 volts.
- Power Outlets: Standard household voltage is 120 volts in the United States and 230 volts in many other countries.
- Car Batteries: Car batteries typically supply around 12 volts.
- Flashlights: Battery-operated flashlights may use 1.5 volts or 3 volts, depending on the battery type.
- Solar-Powered Gadgets: Solar calculators often work with 1.5 volts.
- Wall Chargers: Chargers for smartphones commonly provide 5 volts.
- Power Banks: Power banks can output various voltages, often around 5 volts.
- Electric Vehicles: Electric cars may operate at voltages ranging from 200 to 800 volts.
- Lighting Systems: Standard household light bulbs operate at 120 volts.
- Kitchen Appliances: Voltage for kitchen appliances depends on the device but often falls within the range of 110 to 240 volts.
What is one Volt in simple words?
In simple terms, one volt is a measure of electrical force. It's like the push that makes electricity flow in a circuit. The higher the voltage, the stronger the push, and the more electrical energy can be moved around. In simple words,
- One volt is like the electrical force that pushes energy in a circuit.
- It's similar to a water pump pushing one gallon of water per minute.
- Just as the pump's pushing power is one gallon per minute, one volt is the electrical force moving one unit of energy.
Frequently Asked Questions
| No. | Questions | Answers |
|---|---|---|
| 1 | What happens to current when voltage is increased? | According to Ohm’s law, current increases proportionally with increased voltage, provided resistance remains constant. |
| 2 | What happens to power when voltage is increased? | Power increases proportionally with increased voltage, given that current remains constant, as per the formula P = VI. |
| 3 | What is an ideal voltage source? | An ideal voltage source is a two-terminal element where the voltage is specified at every instant, and it is independent of the current flowing through the source. |
| 4 | Mention common sources of voltage. | Common sources of voltage include batteries and generators. |
| 5 | What are the types of voltage sources? | Two types: independent (alternating and direct) and dependent (voltage-controlled and current-controlled) voltage sources. |