If you need to bring the units of measurement of power into one system, our conversion of power - an online converter will come in handy. And below you can read how the power is measured.

Watt hp metric hp English Erg per second kg-force meter per second

Power is a physical quantity equal to the ratio of the work performed over a certain period of time to this period of time.

How is power measured?

The units of power measurement that are known to every student and are accepted in the international community are watts. Named in honor of the scientist J. Watt. Indicated by Latin W or W.

1 Watt is a unit of measurement of power at which work equal to 1 joule occurs per second. A watt is equal to the power of a current, the strength of which is 1 ampere, and the voltage is 1 volt. In technology, as a rule, megawatts and kilowatts are used. 1 kilowatt is equal to 1000 watts.
Power is also measured in erg per second. 1 erg per second Equal to 10 to the seventh power of a watt. Accordingly, 1 watt is equal to 10 to the seventh power of erg / sec.

And also the unit of measurement of power is considered to be off-system "horsepower". It was introduced into circulation in the eighteenth century and continues to be used in the automotive industry to this day. It is designated as follows:

• L.S. (in Russian),
• HP (in English).
• PS (in German),
• CV (in French).

When translating power, remember that in runet there is an unimaginable confusion when converting horsepower to watts. In Russia, the CIS countries and some other countries, 1 hp. equals 735.5 watts. In England and America, 1 hp equals 745.7 watts.

Hello! To calculate a physical quantity called power, use the formula, where the physical quantity - the work is divided by the time during which this work was done.

It looks like this:

P, W, N = A / t, (W = J / s).

Depending on the textbooks and sections of physics, the power in the formula can be denoted by the letters P, W or N.

Most often, power is used in such branches of physics and science as mechanics, electrodynamics and electrical engineering. In each case, the cardinality has its own formula for calculating. For alternating and direct current, it is also different. Power meters are used to measure power.

Now you know that power is measured in watts. In English, watt - watt, international designation - W, Russian abbreviation - W. This is important to remember, because all household appliances have such a parameter.

Power is a scalar quantity, it is not a vector, as opposed to a force that can have a direction. In mechanics, the general form of the power formula can be written as follows:

P = F * s / t, where F = A * s,

From the formulas it can be seen how instead of A we substitute the force F multiplied by the path s. As a result, power in mechanics can be written as force multiplied by speed. For example, a car with a certain power is forced to slow down when driving uphill, as this requires more power.

The average human power is taken as 70-80 W. The power of cars, airplanes, ships, missiles, and industrial installations is often measured in terms of horsepower. Horsepower was used long before the introduction of watts. One horsepower is equal to 745.7W. Moreover, in Russia it is accepted that l. With. equal to 735.5 watts.

If you are suddenly accidentally asked 20 years later in an interview among passers-by about power, and you remember that power is the ratio of work A, performed per unit time t. If you can put it that way, pleasantly surprise the crowd. Indeed, in this definition, the main thing to remember is that the divisor here is work A, and the dividend is time t. In the end, having work and time, and dividing the first by the second, we get the long-awaited power.

When choosing in stores, it is important to pay attention to the power of the device. The more powerful the kettle, the faster it will heat the water. The power of an air conditioner determines how much space it can cool without extreme engine stress. The more the power of the electrical appliance, the more current it consumes, the more electricity it will spend, the more the electricity bill will be.

In general, electrical power is determined by the formula:

where I - current strength, U-voltage

Sometimes even it is measured in volt-amperes, writing it down as B * A. The total power is measured in volt-amperes, and in order to calculate the active power, you need to multiply the total power by the efficiency (efficiency) of the device, then we get the active power in watts.

Often, such devices as an air conditioner, refrigerator, iron work cyclically, turning on and off from the thermostat, and their average power over the total operating time may be small.

In alternating current circuits, in addition to the concept of instantaneous power, which coincides with the general physical, there are active, reactive and apparent powers. Full power equal to the sum of active and reactive power.

To measure power, electronic devices are used - Wattmeters. The unit of measurement, Watt, got its name in honor of the inventor of the improved steam engine, which revolutionized the power plants of that time. Thanks to this invention, the development of industrial society accelerated, trains, steamships, factories appeared, using the power of a steam engine to move and manufacture products.

We have all come across the concept of power many times. For example, different cars are characterized by different power engine. Also, electrical appliances can have different capacities, even if they have the same purpose.

Power is a physical quantity that characterizes the speed of work.

Respectively, mechanical power is a physical quantity that characterizes the speed of mechanical work:

That is, power is work per unit of time.

SI power is measured in watts: [ N] = [Wt].

1 W is 1 J work done in 1 s.

There are other units of measure for power, for example, such as horsepower:

It is in horsepower that the power of a car engine is most often measured.

Let's get back to the formula for the power: The formula by which the work is calculated is known to us: Therefore, we can transform the expression for the cardinality:

Then, in the formula, the ratio of the displacement modulus to the time interval is formed. This, as you know, is the speed:

Just note that in the resulting formula we use the velocity module, since we have divided not the movement itself, but its module for the time being. So, power is equal to the product of the modulus of force, modulus of speed and the cosine of the angle between their directions.

This is quite logical: for example, the power of the piston can be increased by increasing the force of its action. By applying more force, he will do more work in the same time, that is, he will increase the power. But even if you leave the force constant and make the piston move faster, it will undoubtedly increase the work done per unit of time. Consequently, the power will increase.

Examples of problem solving.

Objective 1. The power of the motorcycle is 80 hp. Moving along a horizontal section, the motorcyclist develops a speed of 150 km / h. At the same time, the engine runs at 75% of its maximum power... Determine the frictional force on the motorcycle.

Objective 2. The fighter, under the influence of a constant thrust force directed at an angle of 45 ° to the horizon, accelerates from 150 m / s to 570 m / s. In this case, the vertical and horizontal speed of the fighter increases by the same value at each moment of time. The mass of the fighter is 20 tons. If the fighter accelerated within one minute, what is the power of its engine?

In 1882, the British Science Association decided to start using a new unit of measurement called the watt. What is it used for today, what is it equal to and by what formula can it be calculated? Let's find the answers to all these questions.

Watt is a unit of measure for what?

Since then fateful year When the British introduced the tradition of using the watt, gradually the whole world began to switch to it, instead of outdated and impractical horsepower. With the advent of the SI system, it was introduced into it and began to be used everywhere.

So, what physical quantity has a unit of measurement "watt"? Remember the lessons of physics: the correct answer to this question is power.

Watt got its name in honor of his "father" - the Scotsman James Watt. In abbreviation, this unit is always written with a capital letter - W (W - according to international standards of the SI system), and completely - with a small "watt" (watt).

Being not a basic, but a derived unit (according to the SI standard), the unit in question depends on the meter, kilogram and second. In practice, this means that one watt is the power at which one joule of work is performed in one second of time. That is, the following dependence is obtained: 1W = 1J / 1s = 1H x m / s = kg x m 2 / s 3 = kg x m 2 x s -3.

In addition to those listed above, watt is associated with non-system units. For example, with a calorie. So 1 W = 859.845227858985 cal / hour. This ratio is important when it comes to calculating the amount of heat generated by an electric heater.

Formula

So, watt is a unit of measure for power. Let's look at what formula it can be calculated.

As mentioned above, the power depends on the work and the time. The following formula is obtained: P = A / t (power is equal to the quotient of the division of work by time).

Knowing that the formula of work is equal to: A = F x S (where F is force, S is distance), you can use this data.

As a result, we get the formula: P = F x S / t. And since S / t is speed (V), then the power can be calculated like this: P = F x V

Interdependence of ampere, watt, volt

The unit of measurement that we are considering is directly related to such quantities as voltage (measured in volts) and current (measured in amperes).

1 watt is constant power electric current at a voltage of 1 V and a force of 1 A.

In the form of a formula, it looks like this: P = I x U.

Watts, kilowatts, megawatts and microwatts

Having learned that a watt is a unit of measure for power, what quantities it depends on and what formulas it is easier to calculate, it is worth paying attention to concepts such as kilowatts, megawatts and microwatts.

Since W is a very modest value (such is the transmitter power of any mobile phone), in the electric power industry it is more common to use the kilowatt (kW).

Judging by the standard “kilo” prefix for the SI system, we can conclude that 1 kW = 1000 W = 10 3 W. Therefore, to convert watts to kilowatts, you just need to divide their number by a thousand, or vice versa, if kilowatts are converted to watts.

For example, a typical passenger car has a capacity of 60,000 watts. To translate this into kilowatts, you need to divide 60,000 by 1000 and the result is 60 kW.

Kilowatts are the accepted unit for measuring the power of electricity. In this case, a large multiple of the watt is sometimes used. We are talking about a megawatt - MW. It is equal to 1,000,000 watts (10 6) or 1,000 kilowatts (10 3).

For example, the British Eurostar electric train has a capacity of 12 megawatts. That is, it is 12,000,000 watts. Not surprisingly, it is the fastest in the UK.

Despite its modest size, sometimes this unit turns out to be too large to measure the power of certain objects, therefore, along with multiples in the C system, sub-multiples of a watt are also allocated. The most commonly used of these is microwatt (μW - written with a lowercase letter so as not to be confused with megawatt). It is equal to one millionth of a watt (10 -6). Typically, this unit is used when calculating the power of electrocardiographs.

In addition to the three above, there are about two dozen other multiples and sub-multiples of watt units. However, they are most often used in theoretical calculations, and not in practice.

Watt hour

Considering the features of the watt (power unit), let's pay attention to the watt-hour (Wh). This term is used to measure a quantity such as energy (sometimes work is measured in watt-hours).

1 watt hour equal to the number work performed for one hour at a power of 1 watt.

Since the unit in question is quite small, the kilowatt-hour (kWh) is often used to measure electricity. It is equal to 1000 watt-hours or 3600 W s.

Please note that the power generated at power plants is measured in kilowatts (sometimes megawatts), but for consumers its amount is calculated in kilowatt-hours (less often in megawatt-hours when it comes to megacities or huge enterprises).

Note that besides the kilowatt-hour and megawatt-hour, the watt-hour has exactly the same multiples and sub-multiples as the regular watt.

What device is called a wattmeter

Having compared the definition of a watt (a unit of measurement of power) and a watt-hour (a unit of energy or work), pay attention to such a device as a wattmeter (wattmeter). It is used to measure the active power of an electric current.

A classic device of this kind consists of four contacts, two of which are used to connect the wattmeter to an electrical circuit in series with that part of it, the power consumption of which is being measured at the moment. The other two pins are connected in parallel to it.

Wattmeters are usually created on the basis of electrodynamic mechanisms.

Length and Distance Converter Mass Converter Bulk and Food Volume Converter Area Converter Culinary Recipe Volume and Units Converter Temperature Converter Pressure, Stress, Young's Modulus Converter Energy and Work Converter Power Converter Force Converter Time Converter Linear Velocity Converter Flat Angle Converter thermal efficiency and fuel economy Numbers to converter different systems numerals Converter of units of measurement of information Currency rates Sizes of women's clothing and shoes Sizes men's clothing and Footwear Angular Velocity and Rotation Rate Converter Acceleration Converter Angular Acceleration Converter Density Converter Specific Volume Converter Moment of Inertia Converter Torque Force Converter Torque Converter Specific Heat of Combustion (by Mass) Converter Energy Density and Heat of Combustion (by Volume) Converter Temperature Difference Converter Coefficient of Thermal Expansion Converter Thermal Resistance Converter Thermal Conductivity Converter Specific Heat Capacitance Energy Exposure and Radiation Power Converter Heat Flux Density Converter Heat Transfer Coefficient Converter Volumetric Flow Rate Converter Mass Flow Rate Molar Flow Rate Converter Mass Flux Density Converter Molar Concentration Converter Mass Concentration Converter in Dynamic Solution (absolute) viscosity Kinematic Viscosity Converter Surface Tension Converter Vapor Permeability Converter Vapor permeability and vapor transfer rate Converter Sound level converter Microphone sensitivity converter Sound pressure level (SPL) converter Sound pressure level converter with selectable reference pressure Luminance converter Luminous intensity converter Illumination converter Computer graphics resolution converter Frequency and wavelength converter Optical power in diopters and focal length Optical power in diopters and lens magnification (×) Electric charge converter Linear charge density converter Surface charge density converter Bulk charge density converter Electric current linear current density converter Surface current density converter Electric field strength converter Electrostatic potential and voltage converter Converter electrical resistance Electrical Resistivity Converter Electrical Conductivity Converter Electrical Conductivity Converter Electrical Capacitance Inductance Converter American Wire Gauge Converter Levels in dBm (dBm or dBmW), dBV (dBV), Watts, etc. Magnetomotive Force Converter Magnetic Field Strength Converter Magnetic Flux Converter Magnetic Flux Converter induction radiation. Absorbed Dose Rate Converter ionizing radiation Radioactivity. Radioactive decay Radiation converter. Exposure Dose Converter Radiation. Absorbed Dose Converter Decimal Prefix Converter Data Transfer Typography and Image Processing Unit Converter Timber Volume Unit Converter Calculating Molar Mass Periodic Table of Chemical Elements D. I. Mendeleev

Initial value

Converted value

watt exawatt petawatt terawatt gigawatt megawatt kilowatt hectowatt decawatt deciwatt sanewatt milliwatt microwatt nanowatt picowatt femtowatt attowatt horsepower horsepower metric horsepower boiler horsepower electrical horsepower pumping horsepower British horsepower British horsepower thermal unit (int.) per hour Brit. thermal unit (IT) per minute Brit. thermal unit (IT) per second Brit. thermal unit (thermochemical) per hour Brit. thermal unit (thermochemical) per minute Brit. thermal unit (thermochemical) per second MBTU (international) per hour Thousand BTU per hour MBTU (international) per hour Million BTU per hour ton of refrigeration kilocalorie (IT) per hour kilocalorie (IT) per minute kilocalorie (IT) second kilocalorie (term) per hour kilocalorie (term) per minute kilocalorie (term) per second calorie (IT) per hour calorie (IT) per minute calorie (IT) per second calorie (term) per hour calorie (therm) per minute calorie (therm) per second foot pound-force per hour foot lbf / minute foot lbf / second pound-foot per hour pound-foot per minute pound-foot per second erg per second kilovolt-ampere volt-ampere newton-meter per second joule per second exajoule per second petajoule per second terajoule per second gigajoule per second megajoule per second kilojoule per second hectojoule per second decjoule per second decijoule per second centijoule per second microjoule per second per second nanojoule per second picojoule per second femtojoule per second attojoule per seconds joule per hour joule per minute kilojoule per hour kilojoule per minute Planck power

The principle of operation of the Geiger counter

More about power

General information

In physics, power is the ratio of work to the time it takes to do it. Mechanical work is a quantitative characteristic of the action of force F on the body, as a result of which it moves a distance s... Power can also be defined as the rate at which power is transmitted. In other words, power is a measure of the health of a machine. By measuring the power, you can understand how much and at what speed the work is being done.

Power units

Power is measured in joules per second, or watts. Along with watts, horsepower is also used. Before the invention of the steam engine, the power of engines was not measured, and, accordingly, there were no generally accepted units of power. When the steam engine began to be used in mines, engineer and inventor James Watt began to improve it. In order to prove that his improvements made the steam engine more efficient, he compared its power to the performance of horses, since horses have been used by people for many years, and many could easily imagine how much work a horse could do in a given amount of time. In addition, steam engines were not used in all mines. In those where they were used, Watt compared the power of the old and new models of the steam engine with the power of one horse, that is, with one horsepower. Watt determined this value experimentally by observing the work of draft horses at a mill. According to his measurements, one horsepower is 746 watts. Now it is believed that this figure is exaggerated, and the horse cannot work in this mode for a long time, but they did not change the unit. Power can be used as an indicator of productivity, since as power increases, the amount of work performed per unit of time increases. Many have realized that it is convenient to have a standardized unit of power, so horsepower has become very popular. It began to be used to measure the power of other devices, especially transport. Although watts are used almost as long as horsepower, the automotive industry is more likely to use horsepower, and many buyers have a better understanding of when these units are used to indicate the power of an automobile engine.

Household electrical appliances power

Household appliances are usually marked with wattage. Some luminaires limit the power of the bulbs that can be used in them, for example, no more than 60 watts. This is because higher wattage bulbs generate a lot of heat and the luminaire with the socket may be damaged. And the lamp itself at a high temperature in the lamp will not last long. This is mainly a problem with incandescent bulbs. LED, fluorescent and other lamps usually operate at lower wattage at the same brightness and, if used in luminaires designed for incandescent lamps, there is no power problem.

The more the power of the appliance, the higher the energy consumption and the cost of using the appliance. Therefore, manufacturers are constantly improving electrical appliances and lamps. The luminous flux of lamps, measured in lumens, depends on the wattage, but also on the type of lamp. The higher the luminous flux of the lamp, the brighter its light looks. For people, it is the high brightness that is important, and not the power consumed by the lamp, so lately, alternatives to incandescent lamps are becoming more and more popular. Below are examples of lamp types, their wattage and the luminous flux they generate.

• 450 lumens:
• Incandescent lamp: 40 watts
• Compact fluorescent lamp: 9-13 watts
• LED lamp: 4-9 watts
• 800 lumens:



• Incandescent lamp: 60 watts
• Compact fluorescent lamp: 13-15 watts
• LED lamp: 10-15 watts
• 1600 lumens:
• Incandescent lamp: 100 watts
• Compact fluorescent lamp: 23-30 watts
• LED lamp: 16-20 watts

From these examples, it is obvious that with the same generated luminous flux, LED lamps consume the least energy and are more economical than incandescent lamps. At the time of this writing (2013), the price of LED bulbs is many times the price of incandescent bulbs. Despite this, some countries have banned or are about to ban the sale of incandescent lamps due to their high power.

The power of household electrical appliances may differ depending on the manufacturer, and is not always the same during the operation of the appliance. Below are the approximate capacities of some household appliances.



• Household air conditioners for cooling a residential building, split system: 20-40 kilowatts
• Monoblock window air conditioners: 1-2 kilowatts
• Ovens: 2.1-3.6 kilowatts
• Washers and dryers: 2-3.5 kilowatts
• Dishwashers: 1.8-2.3 kilowatts
• Electric kettles: 1-2 kilowatts
• Microwaves: 0.65-1.2 kilowatts
• Refrigerators: 0.25-1 kilowatts
• Toasters: 0.7-0.9 kilowatts

Power in sports

Performance can be judged by power not only for machines, but also for people and animals. For example, the power at which a basketball player throws the ball is calculated by measuring the force she applies to the ball, the distance the ball flew, and the time that force was applied. There are websites that allow you to calculate work and power during exercise. The user selects the type of exercise, enters height, weight, exercise duration, after which the program calculates the power. For example, according to one of these calculators, the power of a person who is 170 centimeters tall and weighs 70 kilograms, who did 50 push-ups in 10 minutes, is 39.5 watts. Athletes sometimes use devices to measure the power at which muscles are working during exercise. This information helps determine how effective their chosen exercise program is.

Dynamometers

To measure power, use special devices- dynamometers. They can also measure torque and force. Dynamometers are used in various industries, from technology to medicine. For example, they can be used to determine the power of a car engine. Several basic types of dynamometers are used to measure the power of vehicles. In order to determine the engine power using dynamometers alone, it is necessary to remove the engine from the car and connect it to the dynamometer. In other dynamometers, the force to be measured is transmitted directly from the wheel of the vehicle. In this case, the car engine drives the wheels through the transmission, which, in turn, rotate the rollers of the dynamometer, which measures the engine power under various road conditions.

Dynamometers are also used in sports and medicine. The most common type of dynamometer for this purpose is isokinetic. This is usually a sensor-based gym equipment connected to a computer. These sensors measure the strength and power of the entire body or specific muscle groups. The dynamometer can be programmed to issue alarms and warnings if the power has exceeded a certain value. This is especially important for people with injuries during the rehabilitation period, when it is necessary not to overload the body.

According to some provisions of the theory of sports, the greatest sports development occurs at a certain load, individual for each athlete. If the load is not heavy enough, the athlete gets used to it and does not develop his abilities. If, on the contrary, it is too severe, then the results deteriorate due to the overload of the body. Exercise stress during some exercise, such as cycling or swimming, depends on many factors environment such as road conditions or wind conditions. Such a load is difficult to measure, however, you can find out with what power the body resists this load, and then change the exercise pattern, depending on the desired load.

Do you find it difficult to translate a unit of measurement from one language to another? Colleagues are ready to help you. Post a question to TCTerms and you will receive an answer within a few minutes.

Car manufacturers from different countries measure the power of their vehicles in various units. What for? You will find out the answer below.

When reading an article about cars, be sure that you will always come across this data. With which? With car power data. Car engine power is one of the most important indicators that is relevant at any time, in any situation. From both practical and theoretical points of view.

Always up-to-date. According to statistics, one of the most interesting pieces of information about new products for readers lies precisely in the power of car engines. Thus, on a subconscious level, people compare models, their advantages and weaknesses relative to each other, only one parameter - the motor power.

Power per se is a measure of how quickly and how far an engine can physically propel a car forward using torque. In mechanical engineering, this phenomenon is summarized by the concept of the amount of "work" that the power unit of a car must perform in order to propel the car forward. As a measure of measurement, such work has received many different units over time. We will take a closer look at some of them today.

Kilowatts (kW)

From a technical point of view, this form of measurement is the most versatile method for calculating power. It is used by engineers all over the world.

Watt is a SI unit of measurement (International System of Units), which means how much power is required to perform work in 1J per unit of time.

It is mainly used by professionals as a more "correct" power indicator from the point of view of fundamental science. As a unit of measurement in the automotive field, it is used mainly in the Southern Hemisphere, so it has historically developed.

The method of measuring power in kilowatts on cars mainly occurs by finding the amount of torque transmitted from the wheels on a dynamometer, then this equation is used for calculations:

Kilowatts have become a modern measure for fixing the power output of cars and perhaps in the future they will become a generally accepted global measure. At least if you look at any of the official figures offered by automakers, you will definitely see the units of kW of power of internal combustion engines on par with horsepower.

Moreover, as the hype surrounding cars with electric motors begins, the introduction of this form of measurement into use will become even more justified, because the amount of work produced by an electric motor is measured using kWh (kilowatt-hours), which determine how long an electric motor can produce a certain amount of energy, for example, for the movement of a car.

Horsepower (hp)

Introduced into everyday life by the "maestro" and concurrently the creator of productive steam engines - Mr. James Watt - a unit of power based on horsepower is somehow alive to this day, carrying the calculations of a brilliant engineer through the centuries. It is the main unit for measuring the power of cars in many countries, including Russia, it is used not only as a measurement of the power of an internal combustion engine in official documents for car models, but also for calculating taxation in the automotive sector, for example, calculating transport tax.

So what exactly is horsepower (hp)? How did it come about and how is it calculated? How was her appearance related to horses?

Scotland, inventor James Watt brought to mind his first steam device that could help hundreds of industrialists and artisans in their everyday work. And it seems that the engine was good for everyone, but how to explain this to the townsfolk? The answer suggested itself, it was necessary to compare the work of the most widespread at that time "power device" (horse) with the work new car... No sooner said than done, Watt sat down to count.

COUNTING AND COMPARISON OF UNITS OF MEASUREMENT

In most European countries, horsepower is defined as 75 kgf m / s, the power expended with uniform vertical lifting of a 75 kg load at a speed of 1 meter per second with an acceleration of gravity of 9.8 m / s.

In the International Metric System, SI is officially measured in watts. 1 h.p. (metric horsepower) is equal to 735 W or 0.73 kW.

In turn, 1 kW equals 1.35 hp.

Moreover, in the measurement system in the United Kingdom, as well as in the United States, horsepower (hp) equates to 745 watts, which is why there is a slight discrepancy with European "horses". Thus, 1 hp. in the USA is equal to 1.0138 hp. from Europe.

For example, the power of a 3.8 liter engineNissanGT-R is 570 h.p., in kilowatts it will be equal to 419 , in hp 577 units.

See also:

How James Watt introduced steam engines and horsepower

Now no one knows for sure how strong the horses that participated in Watt's experiments were, whether they were in their prime or they were old nags. However, several legends have survived.

According to one of which, a certain brewer, the first buyer of Watt's steam unit, probably in order to bring down the price of the inventor's car, decided to hold a competition. A horse in a brewery powered a water pump, and a brewer wanted to buy a steam engine instead.

In order to win for sure, an industrialist who was not clean on hand chose the strongest horse for competition and, by manipulating the whip and other tools to increase labor productivity, squeezed the maximum efficiency out of the poor beast. In response to the challenge, James Watt, using his machine, exceeded the work performed by the horse, according to some sources, by 1.5 times, which was taken as a sample of a metal device that worked on water vapor.

The second legend, on the contrary, tells us that Watt himself slightly "twisted" the calculations in his favor. It took him to convince the recalcitrant coal mine owners to switch from draft horses to steam engines. In the 18th century, the coal from their mines was lifted by horses with a rope through a system of blocks. Calculating the performance of an average horse, Watt applied a factor of 1.5 multiplying that number, making his machine easily outperforming any horse doing the same job.

Since horsepower has spread significantly across the globe due to the simplicity of calculations and understandability for users, various types (definitions) of horsepower have appeared: metric horsepower, mechanical horsepower, boiler hp, electric hp and water horsepower.

Perhaps in some articles and news, both foreign and domestic, you have repeatedly come across incomprehensible abbreviations, for example: nhp,rhp, bhp, shp, ihp, whp... What do they mean?

Nhp orrhp,Nominalhorsepower,ratedhorsepower- net power, used to estimate the power of steam engines.

Bhp,Brakehorsepower- the effective power in hp, the power “removed” from the crankshaft of the internal combustion engine, does not take into account the power loss from the gearbox and transmission of the vehicle.

Shp,Shafthorsepower- engine power on the shaft, this is the power supplied to the propeller shaft, to the turbine shaft or to the output shaft of an automobile gearbox. Gross

Ihp,Indicatedhorsepower- Indicated power in hp, this is the theoretical power of a piston engine, determined by the sum of power from the crankshaft, effective power, and energy consumed for friction.

Power is a physical quantity. It represents the ratio of the work done in a certain period of time and the time period itself. Through work, the change in energy can be measured. Therefore, power shows the rate at which energy is converted in any system.

All these concepts fully apply to electrical power. Here, the work (U) spent on the movement of the 1st pendant is taken into account. Electric current (I) takes into account the number of coulombs moved in one second.

Types of electrical power

Based on the dependence of power on current and voltage, it follows that it can be obtained from high current and low voltage and, conversely, with low current and significant voltage. This effect is used in transformer conversions, when electricity is transmitted over long distances.

Electrical power can be. In the first case, there is an irreversible transformation of this power into another type of energy. To measure it, it is used, which is the product of a volt and an ampere. At power, due to the appearance of inductance, the phenomenon of self-induction occurs. As a result, the electrical energy is partially returned to the grid. In this case, the values ​​of current and voltage are shifted, causing an overall negative effect on the power grid. This type of power is measured in reactive volt-amperes, consisting of the product of the operating current and the voltage drop.

Power unit

Power is one of the basic units used in electrical engineering. The basic unit of measurement is the watt, which reflects the work done over a certain period of time. In production and in domestic conditions, most often, power is measured in, each of which contains 1000 watts. For measuring a large number the power used is megawatts. As a rule, they are applied on different types power plants that generate electricity.

The power of consumers is indicated on special plates or in technical passport devices. Knowing in advance the value of this parameter, it is possible to calculate other indicators of the electrical network - voltage and the amount of current consumed.

How to determine the power of the current