Skip to content
Electricalterminology

Electricalterminology

Best Blog for Basic Electrical Knowledge

Primary Menu
  • Electric
  • Manufacturers & Brands
  • Electronics
  • About Us
  • Contact
  • Affiliate Disclosure
  • Home
  • Electric
  • Powering Up: Comparing Amps, Volts, Ohms, and Watts
  • Electric

Powering Up: Comparing Amps, Volts, Ohms, and Watts

electricalterminology 2 years ago
What are amperes volts ohms and watts

Amps, volts, ohms, and watts are the basics of electrical engineering. If you have studied electrical science, electrical principles, or electronics beyond the school level then you will already be familiar with many of these concepts. On the other hand, if you are returning to study or are a newcomer to electronics or electrical technology these basic definitions will help you get up to speed. Below I did the comparison of these terms with their formulas.

What is Ampere?

The flow of electrical current is measured in amperes, abbreviated as “A” or “I”  (Intensity of current). It may be referred to as amperage (or amp), which is the rate at which electric current flows through a conductor per second. One amp of current is approximately 6,280,000,000,000,000,000 electrons passing any particular point in a  conductor per second.

An ammeter is used to measure this electrical current flow. The current must pass through the meter to measure the current. If no current is flowing, the ammeter measures “0.”

Amps measure how “fast” electricity is moving through a circuit. If equated to a river, the amps in an electrical circuit would be how fast the water in the river is moving.

Formulas:

I = E / R

I = P / E

I = √P / R

E= Voltage (Volts)

I = Current (Amperes)

R= Resistance (Ohms)

P = Power (Watts)

What is Volt?

The volt, abbreviated as “V” or “E” (Electromotive Force), is the unit of measure of electrical voltage (pressure) or the pressure being applied to force electrons through a circuit. Volts can be measured with a voltmeter.

Volts measure the strength of a power source (battery, wall outlet in your house). If equated to a river, the voltage of an electrical circuit would be how wide the river is.

  1. House outlets are between 110 and 125 volts. (in America)
  2. A single “AAA”, “AA”, “C”, or “D” battery are all 1 ½ volt.
  3. Big rectangular-shaped “lantern” batteries are 6 volts.
  4. Small rectangular-shaped batteries are 9 volts.
  5. A car battery is 12 volts.

When higher voltage is used, the device being powered will do more work. For example, a motor will turn faster, or a light bulb will give off more light. However, if you use too much voltage, the light bulb will burn out, the wire will melt, or the motor will “burn out”.

Formulas:

E = I x R

E = P / I

E = √P x R

E= Voltage (Volts)

I = Current (Amperes)

R= Resistance (Ohms)

P = Power (Watts)

What is Ohm?

The unit of measure of electrical resistance is known as an ohm (abbreviated as “R” for resistance). The Greek letter omega (S) is used as the symbol for electrical resistance.

The movement of electrons along a conductor meets with some opposition.  This opposition is known as resistance.  Resistance can be useful in electrical work.  Resistance makes it possible to generate heat, control current flow, and supply the correct voltage to a device.

Ohms measure how much “resistance” there is in the circuit to “slow down” the electricity. If equated to a river, the ohms in an electrical circuit are like a dam on the river. Circuits with lots of ohms need higher voltage to do the same amount of work (power a motor at the same speed for example.)

The amount of resistance (ohm) in a conductor is determined by:

  1. The material of which the conductor is made
  2. The size of the conductor
  3. The length of the conductor
  4. Temperature

Resistance is proportional to the length and size of the conductor. If the length of the wire is doubled, the resistance is doubled. If the diameter wire is reduced by half, then the resistance is doubled. The relationship between amps (electric current), volts (electromotive force), and resistance is called Ohm’s law. Ohm’s law states that volts are equal to amperes times resistance.

Formulas:

E = I x R or  I = E / R or R = E / I

E= Voltage (Volts)

I = Current (Amperes)

R= Resistance (Ohms)

P = Power (Watts)

The Ohm’s law equation can be rearranged to solve for any of the three values as long as the other two values are known. For example, the resistance in a 6-volt circuit, if 2 amperes of current are flowing in the circuit is 3 ohms.

What is Watt?

Electric power is measured in watts, abbreviated as W. It may be referred to as wattage. When applied to electrical equipment, it is the rate that electrical energy is transformed into some other form of energy such as light.

Watts may be compared to the work done by water in washing a car. Keep in mind that amperes are current flow and volts are the electrical pressure. Neither amperes nor volts by themselves give a measure of the amount of power produced for turning motors or producing heat or light. For example, if 15,000 volts were available but no free electron flow or amps, there would be no power.

Also, if there were enough free electrons in a circuit to provide a flow of 3,000 amperes but no volts or pressure, there would be no power to make them flow. The following relationship exists among amperes, volts, and watts:

P = E x I

P = E² / R

P = I² x R

P = Watts

E = Volts

I = Amperes

R = Resistance

Most electrical equipment is rated in watts.

Amperes volts ohms and watts chart

Comparison

Amps vs volts vs ohms vs watts Table

 

 

Continue Reading

Previous: Bypass Contactor & Its Use in a Soft Starter
Next: Din Rail Dimensions and Types of DIN Rails

Related Stories

Advantages and Disadvantages of Incandescent Lamps Advantages and Disadvantages of Incandescent Lamps
  • Electric

Advantages and Disadvantages of Incandescent Lamps

electricalterminology 1 week ago
VFD Parts and Functions VFD Parts: A Guide to Their Essential Functions
  • Electric

VFD Parts: A Guide to Their Essential Functions

electricalterminology 1 week ago
Applications of 3 Phase Induction Motors in Industries Applications of 3-Phase Induction Motors in Industries
  • Electric

Applications of 3-Phase Induction Motors in Industries

electricalterminology 1 week ago
Advantages of DC Motors Advantages of DC Motors: Power and Performance
  • Electric

Advantages of DC Motors: Power and Performance

electricalterminology 1 week ago
Applications of AC Motors Applications of AC Motors: The Versatile Uses of Them
  • Electric

Applications of AC Motors: The Versatile Uses of Them

electricalterminology 2 weeks ago
Advantages of Vacuum Circuit Breakers Advantages of Vacuum Circuit Breakers Explained Technically!
  • Electric

Advantages of Vacuum Circuit Breakers Explained Technically!

electricalterminology 2 weeks ago

Posts List

Advantages of Transducers Advantages of Transducers for Optimal Measurement

Advantages of Transducers for Optimal Measurement

Advantages of Infrared Sensors Advantages of Infrared Sensors: Improved Accuracy and More

Advantages of Infrared Sensors: Improved Accuracy and More

VFD Faults Causes Prevention Techniques VFD Faults: Causes and Prevention Techniques

VFD Faults: Causes and Prevention Techniques

Advantages of PCB Advantages of PCB (Printed Circuit Board) in Electronics

Advantages of PCB (Printed Circuit Board) in Electronics

Diode Failures Causes Prevention Tips Diode Failures: Causes & Prevention Tips

Diode Failures: Causes & Prevention Tips

PLC Selection PLC Selection 101: Tips and Tricks for a Successful Choice

PLC Selection 101: Tips and Tricks for a Successful Choice

Categories

  • Electric
  • Electronics
  • Manufacturers & Brands
  • Uncategorized

Pages

  • About Us
  • Affiliate Disclosure
  • Contact

Recent Posts

  • Advantages of Transducers for Optimal Measurement
  • Advantages of Infrared Sensors: Improved Accuracy and More
  • Advantages and Disadvantages of Incandescent Lamps
  • VFD Parts: A Guide to Their Essential Functions
  • VFD Faults: Causes and Prevention Techniques
Copyright © All rights reserved. | Magnitude by AF themes.