Equivalent Resistance

Water electricity refers to electrical power generated using water, primarily through hydroelectric systems. It converts the kinetic energy of moving or falling water into electricity, providing a renewable and sustainable energy source with low carbon emissions and high efficiency.

What is: “Water Electricity?”

Water electricity, also known as hydroelectric power, is energy derived from moving water. It’s a leading source of renewable electricity worldwide.

✅ Converts water’s kinetic energy into usable electricity

✅ Offers renewable, low-emission electricity generation

✅ Used in dams, rivers, and tidal energy systems

 Most hydroelectric power is generated from the potential energy of dammed water, which drives a water turbine and generator. Less common variations utilize water's kinetic energy or undammed sources, such as tidal power. Hydroelectricity is a renewable energy source.

The energy extracted from water depends not only on the volume but on the difference in height between the source and the water's outflow. This height difference is referred to as the head. The amount of potential energy in water is directly proportional to the head. To obtain a very high head of water for a hydraulic turbine, water may be run through a large pipe called a penstock.

While many supply public power networks, some Water Electricity projects were created for private commercial purposes. For example, aluminum processing requires substantial amounts of power, and in Britain's Scottish Highlands, there are examples at Kinlochleven and Lochaber, designed and constructed during the early 20th century. Similarly, the 'van Blommestein' lake, dam and power station were constructed in Suriname to provide power for the Alcoa aluminum industry. In many parts of Canada (specifically, the provinces of British Columbia, Manitoba, Ontario, Quebec, and Newfoundland and Labrador), hydroelectricity is used so extensively that the word "hydro" is often used to refer to any power delivered by a power utility. The government-run power utilities in these provinces are called BC Hydro, Manitoba Hydro, Hydro One (formerly "Ontario Hydro"), Hydro-Québec and Newfoundland and Labrador Hydro, respectively. Hydro-Québec is the world's largest hydroelectric generating company, with a total installed capacity (2005) of 31,512 MW. For deeper insight into how to generate electricity from various sources, including water, visit our guide on hydroelectricity, which explains methods, systems, and real-world examples.

Importance

Water and Electricity power supplies 20% of the world's electricity. Norway produces virtually all of its energy from hydroelectric sources. In contrast, Iceland produces 83% of its requirements (as of 2004), and Austria generates 67% of all power in the country from hydroelectric sources (over 70% of its total requirements). Canada is the world's largest producer of Water Electricity, and produces over 70% of its electric power from hydroelectric sources.

Apart from a few countries with an abundance of it, hydro capacity is normally applied to peak-load demand, because it can be readily stored during off-peak hours (in fact, pumped-storage hydroelectric reservoirs are sometimes used to store power produced by thermal plants for use during peak hours). It is not a major option for the future in developed countries because most major sites in these countries that have the potential for harnessing gravity in this way are either already being exploited or are unavailable for other reasons, such as environmental considerations.

Regions where thermal plants provide the dominant supply of power utilize Water Electricity to provide the important functions of load following and regulation. This permits thermal plants to be operated closer to thermodynamically optimal points rather than varied continuously, which reduces efficiency and potentially increases pollutant emissions. Concurrently, hydro plants are then utilized to provide for hour-to-hour adjustments and to respond to changes in system frequency and voltage (regulation), with no additional economic or environmental effect.

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Geothermal electricity delivers renewable baseload power by converting subsurface heat through turbines, generators, ORC binary cycles, and heat exchangers, enabling grid integration, high capacity factor, low emissions, and efficient power plant control systems.

What Is Geothermal Electricity?

Geothermal electricity converts geothermal heat to power using turbines and generators for low-emission baseload.

✅ Uses steam, flash, and binary cycle power plant designs

✅ Employs ORC, heat exchangers, and closed-loop systems

✅ Provides baseload, high capacity factor, and grid stability

Geothermal Electricity is produced through geothermal power plants capturing the thermal energy contained in the Earth. Use of geothermal energy is based thermodynamically on the temperature difference between a mass of subsurface rock and water and a mass of water or air at the Earth's surface. This temperature difference allows production of thermal energy that can be either used directly or converted to mechanical or Geothermal Electricity. For context on broader methods and terminology, see this overview of electricity generation and how heat energy is converted to power.

Commercial exploration and development of Plant Geothermal water generated into Electricity to date have focused on natural geothermal reservoirs—volumes of rock at high temperatures (up to 662°F or 350°C) and with both high porosity (pore space, usually filled with water) and high permeability (ability to transmit fluid). The thermal energy is tapped by drilling wells into the reservoirs. The thermal energy in the rock is transferred by conduction to the fluid, which subsequently flows to the well and then to the Earth's surface where it can be converted into Geothermal Electricity. This well-to-turbine pathway is a fundamental part of electricity production from thermal resources.

There are several types of natural geothermal reservoirs. All the reservoirs developed to date for electrical energy are termed hydrothermal convection systems and are characterized by circulation of meteoric (surface) water to depth. The driving force of the convection systems is gravity, effective because of the density difference between cold, downward-moving, recharge water and heated, upward-moving, thermal water. A hydrothermal convection system can be driven either by an underlying young igneous intrusion or by merely deep circulation of water along faults and fractures. Depending on the physical state of the pore fluid, there are two kinds of hydrothermal convection systems: liquid-dominated, in which all the pores and fractures are filled with liquid water that exists at temperatures well above boiling at atmospheric pressure, owing to the pressure of overlying water; and vapor-dominated, in which the larger pores and fractures are filled with steam. Liquid-dominated reservoirs produce either water or a mixture of water and steam, whereas vapor-dominated reservoirs produce only steam, in most cases superheated. Because water acts as the primary working fluid in most systems, understanding the interplay of water and electricity helps clarify operational safety and design.

These hydrothermal systems are distinct from hydroelectricity produced by river impoundments, even though both ultimately rely on water as a medium.

Although geothermal energy is present everywhere beneath the Earth's surface, its use is possible only when certain conditions are met: (1) The energy must be accessible to drilling, usually at depths of less than 2 mi (3 km) but possibly at depths of 4mi (6–7km) in particularly favorable environments (such as in the northern Gulf of Mexico Basin of the United States). (2) Pending demonstration of the technology and economics for fracturing and producing energy from rock of low permeability, the reservoir porosity and permeability must be sufficiently high to allow production of large quantities of thermal water. (3) Since a major cost in geothermal development is drilling and since costs per meter increase with increasing depth, the shallower the concentration of geothermal energy the better. (4) Geothermal fluids can be transported economically by pipeline on the Earth's surface only a few tens of kilometers, and thus any generating or direct-use facility must be located at or near the geothermal anomaly. When these conditions align, engineered systems can efficiently generate electricity from accessible geothermal gradients.

The use of geothermal energy for Geothermal Electricity has become widespread because of several factors. Countries where geothermal resources are prevalent have desired to develop their own resources in contrast to importing fuel for power generation. In countries where many resource alternatives are available for power generation, including geothermal, geothermal has been a preferred resource because it cannot be transported for sale, and the use of geothermal energy enables fossil fuels to be used for higher and better purposes than power generation. Also, geothermal steam has become an attractive power generation alternative because of environmental benefits and because the unit sizes are small (normally less than 100 MW). Moreover, geothermal plants can be built much more rapidly than plants using fossil fuel and nuclear resources, which, for economic purposes, have to be very large in size. Electrical utility systems are also more reliable if their power sources are not concentrated in a small number of large units. In energy planning, geothermal is often evaluated alongside other forms of alternative electricity to balance portfolios and grid resilience. Many developers also highlight its contribution to green electricity targets thanks to low lifecycle emissions.

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Types of resistors are essential in electronics, as they control current, reduce voltage, and ensure circuit stability. From fixed and variable resistors to specialized forms like thermistors and photoresistors, each type plays a critical role in electrical engineering.

What are the Various Types of Resistors?

Types of resistors describe categories of electronic components designed to limit current and manage voltage in circuits."
✅ Fixed resistors ensure stable resistance values

✅ Variable resistors adjust resistance as needed

✅ Specialized resistors respond to heat or light

There are two main types of resistors: fixed and variable. Fixed resistors maintain a constant value, while variable resistors can be adjusted to suit changing requirements. Within these groups are many designs crafted from various materials, each selected for its precision, stability, and suitability in specific applications. When studying how different resistor types perform, it helps to review Ohm’s Law Formula, which explains the mathematical relationship between voltage, current, and resistance.

In addition to resistors, other passive components, such as capacitors, are equally important for controlling current flow and stabilizing electrical circuits.

Common Types of Resistors

Fixed Types of Resistors

Carbon Film Resistors

Carbon film resistors are inexpensive, reliable, and widely used in general-purpose electronics. By applying a thin carbon layer to a ceramic base, they provide a stable resistance for everyday circuits. While not as precise as modern designs, they remain popular where high accuracy isn’t required.

Carbon Composition Resistors

Once the standard in consumer electronics, carbon composition resistors are now less common, but they still serve in circuits that need high pulse load capacity. They offer durability in the face of sudden surges, although their long-term stability and accuracy are lower than those of newer types.

Metal Film Resistors

Metal film resistors, made by depositing a nickel-chromium alloy onto a ceramic substrate, are prized for their precision. With excellent stability, low noise, and tight tolerances, they are widely chosen for high-frequency and sensitive applications. However, they cannot dissipate as much power as wire-wound resistors and are vulnerable to strong surges.

Metal Oxide Resistors

Using oxides like tin or ruthenium on ceramic, metal oxide resistors are known for their robustness. They combine good tolerance with the ability to withstand high voltages, making them ideal where surge protection is essential. While not as accurate as metal film resistors, they offer higher reliability in demanding conditions.

Wire-Wound Resistors

Built from coiled metal wire wrapped around a ceramic or fibreglass core, wire-wound resistors excel in high-power applications. Their ability to handle large currents and high temperatures makes them indispensable in heavy-duty circuits. Their main drawback is bulk, and at high frequencies, their inductance can interfere with performance.

Metal Strip (Foil) Resistors

Metal strip or foil resistors deliver the highest accuracy and stability, with tolerances as fine as 0.005%. Their precision makes them the component of choice in measurement instruments and high-end electronics. Their primary downsides are cost and limited power dissipation, which restrict their use in everyday applications.

Thick and Thin Film Resistors

Produced by different deposition techniques, thick and thin film resistors serve specialized roles. Thick film designs are durable and suited to power electronics and automotive systems, while thin film types offer high accuracy and stability in precision or high-frequency circuits.

Surface-Mount Resistors (SMDs)

Surface-mount resistors are compact components soldered directly onto printed circuit boards. They make modern electronics smaller and more efficient, and although tiny, they cover a wide range of resistance values to support everything from consumer devices to industrial controls.

Variable Types of Resistors

Engineers often use practical examples to compare the unit of electrical resistance with how resistors function in series and parallel arrangements.

Potentiometers

Potentiometers are adjustable resistors that allow manual control over current or voltage. They are common in volume dials, tuning controls, and adjustable circuits where user input is required.

Light-Dependent Resistors (LDRs)

LDRs change resistance with varying light levels, making them useful in light sensors, alarms, and automatic lighting systems.

Thermistors

Thermistors alter resistance with temperature. Positive temperature coefficient (PTC) types increase resistance as they heat, protecting circuits from over-current, while negative temperature coefficient (NTC) types reduce resistance with rising temperature, making them useful for sensing and regulation.

When considering the various types of resistors, they may be simple components, but their diversity makes them essential to every circuit. Whether precision, power handling, or responsiveness to environmental changes is needed, there is a resistor designed for the task. Selecting the right one ensures accuracy, stability, and safety in electronic design.

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Basic electricity refers to the fundamental concepts of electric charge, current, voltage, and resistance. It explains how electric circuits work, how energy flows, and how components like wires, batteries, and switches interact in homes, schools, and industries.

What is Basic Electricity?

Basic electricity refers to the foundational principles that explain how electric energy is generated, transmitted, and used in circuits. When an electric current flows through a conductor, it creates a magnetic field (or “flux”) around it.

✅ Explains current, voltage, resistance, and power in simple terms

✅ Describes how electric circuits operate and transfer energy

✅ Essential for understanding household wiring, batteries, and switches

Understanding the fundamentals of voltage is essential for grasping how electric circuits function — see our full explanation of voltage.

The strength of this magnetic field increases when the conductor is shaped into a coil with multiple turns. In electrical engineering, this coiled conductor is known as an inductor. If a steady direct current (DC) flows through the coil, it forms an electromagnet—an object with magnetic properties that can be switched on and off using a basic electrical switch.

Basic Electrical Theory

There are four basic electrical quantities that we need to know:

• Current

• Potential Difference (Voltage)

• Power

• Resistance

Electrical Current

Current is the movement of electric charge through a conductor. Each electron carries a charge of 1.6 × 10⁻¹⁹ coulombs—too small to measure individually—so we measure charge in groups called coulombs. When 1 coulomb of charge passes through a point in a circuit per second, the current is  1 ampere (A). Electric current is measured in amperes and is essential to the functioning of all electrical systems. Learn how voltage drop affects electrical performance and safety in residential and industrial systems. You can estimate losses in long-distance wiring with our easy-to-use voltage drop calculator. For step-by-step guidance on circuit loss calculations, explore the voltage drop formula explained clearly.

Potential Difference

Voltage, or potential difference, refers to the energy per unit charge in a circuit. It represents the work each charge can perform. Think of voltage as the electrical pressure that pushes electrons through a conductor. Higher voltage means more potential energy available to do work, such as lighting a bulb or powering a motor.

Power in a Circuit

Electrical power is the rate at which energy is used or transferred in a circuit. It can be calculated using the formula:

Power (W) = Voltage (V) × Current (A)

This equation is fundamental in both residential and industrial applications, from estimating energy usage to designing electrical systems.

Electrical Resistant Behaviour

Resistance is the opposition to the flow of electric current. It determines how much current will flow for a given voltage. Materials like copper have low resistance and conduct electricity well, while materials like rubber have high resistance and are used as insulators. Learn how voltage drop affects electrical performance and safety in residential and industrial systems.

Electromagnetic Induction

There’s a reciprocal relationship between electric current and magnetism. When a magnet is moved past a conductor at a right angle, it induces a voltage in the conductor—a principle known as electromagnetic induction. The polarity of the induced voltage depends on the direction and orientation of the magnetic field.

This effect becomes more noticeable when the conductor is formed into a coil. As the north pole of the magnet passes the coil, voltage is induced, and current flows. When the south pole passes, the induced voltage reverses polarity, and the current changes direction. This principle is the foundation of generator operation. You can estimate losses in long-distance wiring with our easy-to-use voltage drop calculator.

The Generator and the Sine Wave

In an electric generator, coils placed on opposite sides of a rotating magnet generate alternating current (AC). These voltages combine, doubling the output. For example, a 120-volt, 60-Hz generator creates a wave that oscillates from +169.7V to -169.7V.

This wave is called a sine wave because the voltage at any point corresponds to the sine of the magnet’s angle of rotation. The cycle repeats 60 times per second in North America (60 Hz), creating the household AC power we are familiar with. For step-by-step guidance on circuit loss calculations, explore the voltage drop formula explained clearly.

Forms of Electricity: AC and DC

Electricity exists in two major forms:

• Alternating Current (AC): The direction of current flow alternates regularly. AC electricity is used in power grids because it is easier to transmit over long distances and is compatible with devices such as transformers and capacitors.

• Direct Current (DC): The current flows steadily in one direction. DC is commonly used inside electronics and battery-powered devices. Unlike AC, the voltage remains constant, making it easy to measure with a DC voltmeter.

AC – Alternating Current

Alternating current is the most common form of electricity used in homes, businesses, and utilities. It alternates direction 50–60 times per second, depending on the region. AC is generated by AC generators and is favored for its ability to change voltage levels easily, making it efficient for transmission over long distances. Sudden dips in power can disrupt equipment — find out what causes voltage sag and how to prevent it.

DC – Direct Current

Direct current flows continuously in one direction. Because its voltage is steady or changes very slowly, it’s easy to measure. It is used in battery-powered systems and internal electronic circuits. Unlike AC, DC cannot be easily stepped up or down in voltage without the use of complex circuitry.

When calculating AC power, engineers use RMS (Root Mean Square) voltage, which gives an effective value comparable to DC. For example, 120V AC RMS is equivalent in power to 120V DC, despite the AC waveform's variations. Discover how water and electricity interact, including safety considerations and risks in common environments.

Transformers and Induction

Transformers, built using coiled wires around iron cores, rely on electromagnetic induction. When AC flows through the primary coil, it creates a changing magnetic field that induces a voltage in the secondary coil. This allows voltage to be stepped up or down for different uses, such as high-voltage transmission or low-voltage device operation.

Atoms, Electrons, and Electric Charge

To fully grasp electricity, it’s essential to understand atomic structure. All matter is made up of atoms, which contain a nucleus of protons (positive) and neutrons (neutral), surrounded by orbiting electrons (negative). The outermost electrons—called valence electrons—can be knocked loose by energy, creating an electric current.

When electrons leave an atom, it becomes positively charged. This movement of charge is the essence of electricity. The ability of atoms to gain or lose electrons determines whether a material is a conductor (like copper) or an insulator (like plastic).

Electrical Charge and Attraction

One universal rule in electricity and magnetism is that like charges repel and opposite charges attract. A positively charged object will attract a negatively charged one. This principle governs everything from how circuits function to how magnetic fields interact with conductors. To understand how energy use is measured over time, read our overview of the watthour meter and its function.

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Power System Analysis enables load flow studies, fault calculations, stability assessment, state estimation, and contingency analysis for grids, integrating SCADA data, protection coordination, and reliability planning to optimize transmission, distribution, and generation performance.

What Is Power System Analysis?

Power System Analysis models grid behavior to ensure stability, reliability, efficiency, and secure operation.

✅ Load flow, short-circuit, and transient stability studies

✅ State estimation, SCADA integration, and contingency analysis

✅ Protection coordination, reliability assessment, and optimization

Power system analysis (PSA) is an essential electrical system component. It helps to ensure that the electrical system operates efficiently, reliably, and safely. Power flow analysis, fault study, stability investigation, renewable energy integration, grid modernization, and optimization techniques are all essential concepts in PSA. As our society continues to rely heavily on electricity, PSA will remain a vital tool for ensuring the stability and reliability of the electrical system. For foundational context on how electricity underpins these studies, see this primer on what electricity is and how it behaves.

One of the critical concepts in PSA is power system modelling. Modelling is creating a mathematical model of the electrical system. This model includes all the system components, such as generators, transformers, transmission lines, and distribution networks. Modelling is essential as it provides a detailed understanding of the system's workings. Engineers commonly begin by drafting a single-line diagram to visualize component interconnections and power paths.

Another critical concept in PSA is power flow investigation, also known as load flow investigation. Power flow analysis calculates the electrical system's voltages, currents, and power flows under steady-state conditions. A power flow study helps determine whether the electrical system can deliver electricity to all the loads without overloading any system component. The results of the power flow investigation are used to plan the system's expansion and ensure that it operates efficiently and reliably. In practice, load-flow outputs are interpreted within the broader context of electric power systems to validate voltage profiles and thermal limits.

Fault study is another crucial component of PSA. A fault study is a process of analyzing the system's behaviour during a fault condition. This needs a short circuit analysis. A fault is abnormal when the system has a short or open circuit. A fault study helps to determine the fault's cause and develop strategies to prevent or mitigate the effects of faults in the future.

Stability investigation is also an important aspect of PSA. Stability investigation is the process of analyzing the system's behaviour under dynamic conditions. For example, the system is subject to dynamic disturbances, such as sudden load or generator output changes, which can cause instability. Stability investigation helps ensure the system can withstand these disturbances and operate reliably.

The transient investigation is another key concept in PSA. The transient study analyzes the electrical system's behaviour during transient conditions, such as switching operations or lightning strikes. A brief investigation helps ensure the system can withstand these transient conditions and operate reliably.

Renewable energy integration is an emerging concept in PSA. As more renewable energy sources, such as wind and solar power, are integrated into the energy system, PSA becomes increasingly essential to ensure the stability and reliability of the electrical system. Understanding how generation mixes are formed benefits from a primer on how electricity is generated across thermal, hydro, and renewable technologies.

Grid modernization is also a crucial aspect of PSA. As the system ages, it becomes increasingly important to modernize the grid to ensure that it can meet the demands of modern society. Therefore, PSA is used to develop strategies to modernize the grid and ensure it operates efficiently, reliably, and safely. Many modernization roadmaps align with the evolving architecture of the electricity grid as utilities adopt automation, advanced metering, and distributed resources.

Finally, protection coordination and optimization techniques are essential components of PSA. Protection coordination involves developing strategies to protect the electrical system from faults and other abnormal conditions. Optimization techniques involve developing strategies to optimize the system's operation and ensure it operates efficiently and reliably. Because reactive power and losses affect dispatch, monitoring and improving power factor can materially enhance system efficiency.

What is power system analysis, and why is it important?

PSA analyzes the electrical system to ensure it operates efficiently, reliably, and safely. Therefore, it is crucial to identify potential problems before they occur and develop strategies to prevent or mitigate the effects of these problems. In addition, PSA is important because it helps ensure that the electrical system can meet the demands of modern society, which relies heavily on electricity.

How is power flow analysis performed?

Power flow analysis, or load flow analysis, is performed using a mathematical model. The model includes all the power system components, such as generators, transformers, transmission lines, and distribution networks. A power flow study calculates the electrical system's voltages, currents, and power flows under steady-state conditions. The results of the power flow investigation are used to plan the electrical system's expansion and ensure that it operates efficiently and reliably. These studies also quantify reactive power behavior, making concepts like what power factor is directly applicable to planning and operations.

What is fault analysis, and how is it used?

Fault analysis is analyzing the system's behaviour during a fault condition. A fault is abnormal when the system has a short or open circuit. A fault study is used to determine the fault's cause and develop strategies to prevent or mitigate the effects of faults in the future. Fault analysis is crucial in ensuring the safety and reliability of the electrical system.

What are the different stability study techniques used?

Several stability investigation techniques are used in PSA to measure transient, small-signal, and voltage stability. Transient stability is used to analyze the behaviour of the distribution under dynamic conditions, such as sudden changes in load or generator output. Small-signal stability measurement analyzes the system's behaviour under small disturbances. Finally, voltage stability measurement is used to analyze the system's behaviour under steady-state conditions and determine the system's voltage limits.

How does renewable energy integration affect power system analysis?

Renewable energy integration is an emerging concept in PSA. As more renewable energy sources, such as wind and solar power, are integrated into the electrical system, PSA becomes increasingly essential to ensure the stability and reliability of the system. Renewable energy sources are intermittent, which can cause fluctuations in the system. PSA is used to develop strategies to integrate renewable energy sources into the system while ensuring its stability and reliability.

What are the challenges of grid modernization, and how does power system analysis help overcome them?

Grid modernization is a crucial aspect of PSA. As the system ages, it becomes increasingly important to modernize the grid to ensure that it can meet the demands of modern society. Grid modernization involves upgrading the system to incorporate new technologies, such as smart grid technologies and renewable energy sources. The challenges of grid modernization include the need for new infrastructure, the integration of new technologies, and new regulatory frameworks. PSA is used to develop strategies to overcome these challenges and to ensure that the electrical system operates efficiently, reliably, and safely.

How can optimization techniques improve system efficiency and reliability in power system analysis?

Optimization techniques can be used in PSA to improve system efficiency and reliability. These techniques involve developing strategies to optimize the system's operation and ensure it operates efficiently and reliably. For example, optimization techniques can determine the optimal generation and transmission of power, improve load forecasting, and develop strategies to reduce energy consumption. PSA is crucial in developing and implementing these optimization techniques, which help improve the electrical system's overall efficiency and reliability, leading to a more sustainable and cost-effective electrical power system.

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Types of electricity include static electricity and current electricity, which flows as direct current (DC) or alternating current (AC). Electricity can be generated from various sources, including solar, wind, and hydro, but all supply either static or current electricity.

What are the Types of Electricity?

There are two types of electricity: Static Electricity and Current Electricity.

✅ Static electricity results from the buildup of electric charges.

✅ Current electricity includes alternating (AC) and direct (DC) flow.

Static Electricity is made by rubbing together two or more objects, creating friction, while Current electricity is the flow of electric charge across an electrical field.

Static Electricity

Static electricity is when electrical charges build up on the surface of a material. It is usually caused by rubbing materials together. The result of a build-up of static electricity is that objects may be attracted to each other or may even cause a spark to jump from one to the other. For Example, rub a balloon on a wool and hold it up to the wall.

Before rubbing, like all materials, the balloons and the wool sweater have a neutral charge. This is because they each have an equal number of positively charged subatomic particles (protons) and negatively charged subatomic particles (electrons). When you rub the balloon with the wool sweater, electrons are transferred from the wool to the rubber because of differences in the attraction of the two materials for electrons. The balloon becomes negatively charged because it gains electrons from the wool, and the wool becomes positively charged because it loses electrons.

Current Electricity

Current is the rate of flow of electrons. The movement of electrons produces it, and it is measured in amperes. Unlike static electricity, current electricity must flow through a conductor, usually copper wire. Electricity is similar to the flow of water in a river. The river flows from one spot to another, and the speed of the current determines the speed at which it moves. With electricity, current is a measure of the amount of energy transferred over a period of time. That energy is referred to as an electron flow. One of the results of the current is the heating of the conductor. When an electric stove heats up, it's because of the flow of current.

There are various sources of current electricity, including the chemical reactions that occur in a battery. The most common source is the generator. A simple generator produces electricity when a coil of copper turns inside a magnetic field. In a power plant, electromagnets spinning inside many coils of copper wire generate vast quantities of electricity.

There are two main kinds of electric current. Direct (DC) and Alternating (AC). It's easy to remember. Direct current is similar to the energy you obtain from a battery. Alternating current is like the plugs in the wall. The big difference between the two is that DC is a flow of energy, while AC can turn on and off. AC reverses the direction of the electrons.

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