Resistor colour Code of learn.

Resistor Colour Code of learn.
 

HOW TO REMEMBER THE COLOUR CODE

Resistance colour     value   

    black                       0   
    brown                      1
    red                           2                                           
   orange                      3                                  
    yellow                     4   
    green                       5   
    blue                         6
    violet                       7     
    gray                         8     
    white                       9
    silver                      -2   
    gold                        -1

 
      Here are some common ways to remember the colour code:
    
     Resistance is measured in OHMs.
     
 Resistors have RESISTANCE and the main purpose of a resistor is to reduce the CURRENT FLOW.

    "Ohm." but this symbol is not available on some word-processors, so the letter "R" is used. 
 The letter "E" is also sometimes used and both mean "Ohms."

    A one-ohm resistor is written "1R" or "1E."  It can also be written "1R0" or "1E0."
    
    A resistor of one-tenth of an ohm is written  "0R1" or "0E1."  
 The letter takes the place of the decimal point.
    10 ohms  =  10R
    100 ohms = 100R
    1,000 ohms = 1k (k= kilo = one thousand)
    10,000 ohms = 10k
    100,000 ohms = 100k
    1,000,000 ohms = 1M   (M = MEG = one million)

    Every resistor is identified by colour bands on the body, but when the resistor is a surface-mount device, numbers are used and sometimes letters.
    You MUST learn the colour code for resistors.
      
    Reading 4-band resistors.
    The most "common" type of resistor has 4 bands and is called the 10% resistor.
 It now has a tolerance of 5% but is still called the "10% type" as the colours increase by 20% so that a resistor can be 10% higher or 10% lower than a particular value and all the resistors produced in a batch can be used.

    The first 3 bands produce the resistance and the fourth band is the "tolerance" band. Gold = 5%
    (Silver =10% but no modern resistors are 10%!! - they are 5%  2% or 1%

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what is ton?

what is ton?
Ton is 1000kg and 25 mun is ton in Pakistan

 The ton is a unit of measure. It has a long history and has acquired a number of meanings and uses over the years. It is used principally as a unit of mass, and as a unit of volume. It can also be used as a measure of energy, for truck classification, or as a colloquial term.

A ton of refrigeration (commonly abbreviated as TR) is a unit of power used in some countries (especially in North America) to describe the heat-extraction capacity of refrigeration and air conditioning equipment. It is defined as the heat of fusion absorbed by melting 1 short ton (2,000 lb; 0.893 long tons; 0.907 t) of pure ice at 0 °C (32 °F) in 24 hours.[1][2] It is equivalent to the consumption of one ton of ice per day and originated during the transition from stored natural ice to mechanical refrigeration.

A refrigeration ton is approximately equivalent to 12,000 BTU/h or 3.517 kW. Air-conditioning and refrigeration equipment capacity in the U.S. is often specified in "tons" (of refrigeration). Many manufacturers also specify capacity in BTU/h, especially when specifying the performance of smaller equipment.    (TJK)

1ton = 12000 British thermal unit (BTU)

1.5 ton = 18000 British thermal unit (BTU)

2 ton = 24000 British thermal unit (BTU)     (TJK)

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what is BTU ?

                                                  What is BTU?
                      BTU is British thermal unit.

 
British thermal unit
The British thermal unit (BTU or Btu) is a traditional unit of energy equal to about 1055 joules. It is the amount of energy needed to cool or heat one pound of water by one degree Fahrenheit (Physical analogue; one four inch, wooden kitchen match consumed completely generates 1 BTU).
 In science, the joule, the SI unit of energy, has largely replaced the BTU.
The BTU is most often used as a measure of power (as BTU/h) in the power, steam generation, heating, and air conditioning industries, and also as a measure of agricultural energy production (BTU/kg).[verification needed] It is still used in metric English-speaking countries (such as Canada), and remains the standard unit of classification for air conditioning units manufactured and sold in many non-English-speaking metric countries.[1] In North America, the heat value (energy content) of fuels is expressed in BTUs

Contents
    1 Definitions   
2 For natural gas     
    3 Associated units
 
Definitions
A BTU is the amount of heat required to raise the temperature of 1 avoirdupois pound of liquid water by 1 degree Fahrenheit at a constant pressure of one atmosphere.[2][3] As with the calorie, several definitions of the BTU exist, because the temperature response of water to heat energy is non-linear. This means that the change in temperature of a water mass caused by adding a certain amount of heat to it will be a function of the water's initial temperature. Definitions of the BTU based on different water temperatures can therefore vary by up to 0.5%. A BTU can be approximated as the heat produced by burning a single wooden match[4] or as the amount of energy it takes to lift a one-pound weight 778 feet (237 m).[5]
Nominal temperature     BTU equivalent in joules     Notes
39 °F (3.9 °C)     ˜ 1059.67     Uses the calorie value of water at its maximum density (4 °C or 39.2 °F)
Mean     ˜ 1055.87     Uses a calorie averaged over water temperatures 0 to 100 °C (32.0 to 212.0 °F)
IT     = 1055.05585262     The most widespread BTU uses the International Steam Table (IT) calorie, which was defined by the Fifth International Conference on the Properties of Steam (London, July 1956) to be exactly 4.1868 J
ISO     = 1055.056     International standard ISO 31-4 on Quantities and units—Part 4: Heat,[6] Appendix A. This value uses the IT calorie and is rounded to a realistic accuracy
59 °F (15.0 °C)     = 1054.804     Chiefly American. Uses the 15 °C calorie, itself now defined as exactly 4.1855 J (comité international 1950; PV, 1950, 22, 79–80)
60 °F (15.6 °C)     ˜ 1054.68     Chiefly Canadian
63 °F (17.2 °C)     ˜ 1054.68   
Thermochemical ("Th"[7])     = 1054.35026444     Uses the "thermochemical calorie" of exactly 4.184 J
The unit M Btu or m Btu was defined as one thousand BTU, presumably from the Roman numeral system where "M" or "m" stands for one thousand (1,000). This notation is easily confused with the SI mega- (M) prefix, which denotes multiplication by a factor of one million (×106),
 or with the SI milli- (m) prefix, which denotes division by a factor of one thousand (×10-3). To avoid confusion, many companies and engineers use the notation MM Btu or mm Btu to represent one million BTU (although, confusingly, MM in Roman numerals would traditionally represent 2,000) and in many contexts this form of notation is deprecated and discouraged in favour of the more modern SI prefixes. Alternatively, the term therm may be used to represent 100,000 (or 105) BTU, and quad for 1015 BTU. Some companies also use BtuE6 in order to reduce confusion between 103 BTU and 106 BTU.[8]

For natural gas
    In natural gas, by convention 1 MM Btu (1 million BTU)
    The energy content (high or low heating value) of a volume of natural gas varies with the composition of the natural gas, which means there is no universal conversion factor for the number of BTU to volume. 1 standard cubic foot of average natural gas yields ˜ 1030 BTU (between 1010 BTU and 1070 BTU, depending on quality, when burned)
    As a coarse approximation, 1000 ft3 of natural gas yields ˜ 1 MMBTU
    1 ft3 of natural gas yields ˜ 1000 BTU
    For natural gas price conversion 1000 m3 ˜ 35.8 MM BTU and 1 MM BTU ˜ 27.9 m3
As a unit of power
When used as a unit of power for heating and cooling systems, BTU per hour (BTU/h) is the correct unit, though this is often abbreviated to just "BTU".[verification needed].

    1 watt is approximately 3.41214 BTU/h[10]
    1000 BTU/h is approximately 293.071 W
    1 horsepower is approximately 2544 BTU/h

Associated units
    1 ton of cooling, a common unit in North American refrigeration and air conditioning applications, is 12,000 BTU/h (3.52 kW). It is the amount of power needed to freeze 1 short ton (0.893 long tons; 0.907 t) of water into ice in 24 hours.
    1 therm is defined in the United States and European Union as 100,000 BTU—but the U.S. uses the BTU59 °F while the EU uses the BTU IT. The therm is used to price natural gas.[11]
    1 quad (short for quadrillion BTU) is 1015 BTU, which is about  (1.055×1018 J). Quads are used in the United States for representing the annual energy consumption of large economies: for example, the U.S. economy used 99.75 quads in 2005.[12] One quad/year is about 33.43 gigawatts.

The BTU should not be confused with the Board of Trade Unit (B.O.T.U.), which is a much larger quantity of energy (1 kWh or 3,412 BTU).

The BTU is often used to express the conversion-efficiency of heat into electrical energy in power plants. Figures are quoted in terms of the quantity of heat in BTU required to generate 1 kWh of electrical energy. A typical coal-fired power plant works at 10,500 BTU/kWh, an efficiency of 32–33%.[13]   (TJK)

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Why is Air conditioner and Refrigeration British thermal unit (BTU) and Ton; and what is Amps.

 Why is Air conditioner and Refrigeration British thermal unit
 (BTU) and Ton; and what is Amps


 0.75 Ton =9000 British thermal unit (BTU)=4.5Amps
           
     1 Ton = 12000 British thermal unit (BTU) = 6 Amps

  1.5 Ton = 18000 British thermal unit (BTU) = 9 Amps

     2 Ton =24000 British thermal unit (BTU) = 12 Amps
 
  2.5 Ton = 30,000 British thermal unit (BTU) = 15 Amps

     3 Ton = 36,000 British thermal unit (BTU) = 18 Amps'

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What size generator do I need to run 2 ton ac unit?

What size generator do I need to run 2 ton ac unit?
                                                                    Generator

    1    0.75 Ton =9000 British thermal unit (BTU)=4.5Amps only 3kw or 3.5 kva Generator

    2     1 Ton = 12000 British thermal unit (BTU) = 6 Amps only 3.5 kw or 4kva Generator

   3     1.5 Ton = 18000 British thermal unit (BTU) = 9 Amps only 5kw or 6kw or 6.5 kva Generator

   4     2 Ton =24000 British thermal unit (BTU) = 12 Amps only 8kw or10 kva Generator

   5    2.5 Ton = 30,000 British thermal unit (BTU) = 15 Amps only12kw or 15kva Generator

   6    3 Ton = 36,000 British thermal unit (BTU) = 18 Amps only 15 kw or  17 kva Generator

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Why is a 10 hp engine needed to run a generator that produces 5 kw of power?

Why is a 10 hp engine needed to run a generator that produces
 5 kw of power?

1kw = 1.75hp + 0.75 = 1kw Generator
 +2 hp engine 

 1  10 hp engine - dynamo 5 kw = Generator 5kw
2  20 hp engine-dynamo10 kw = Generator10kw
3  30 hp engine-dynamo15 kw = Generator 15kw
4  40 hp engine-dynamo 20 kw = Generator20kw
5  50 hp engine-dynamo 25kw = Generator 25kw
6  60 hp engine-dynamo 30kw = Generator 30kw
7  70 hp engine-dynamo 35kw = Generator 35kw
8  80 hp engine-dynamo 40kw = Generator 40kw
9  90 hp engine-dynamo 45kw = Generator 45kw
10  100 hp engine-dynamo50kw=Generator50kw
11  200 hp engine - dynamo 100 kw = Generator 100kw

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A Complete Guide about Solar Panel Installation. Step by Step Procedure with Images

                 TJK SOLAR ELECTRIC SYSTEMS INFORMATION
          

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