DC theory level 1 second edition lesson 4 conductor resistance and wattage loss
if a 250 foot number 12 copper conductor has a resistance of 0.397 ohms how much is the resistance of the same conductor at 800 ft
1.27 ohms 0.397/250 = x/800 multiply both sides by 800 to get X by itself
what is the resistance of a 600-foot number 12 aluminum conductor? The resistance of the conductor is 3.18 ohms / 1000 feet
1.91 ohms 3.18/1000 = x/600 multiply both sides by 600 to get X by itself
each kilowatt hour equals?
1000 watt hours
calculate the resistance of a piece of aluminum wire with a diameter of 100 mils and a length of 2 miles at 68 degrees Fahrenheit. be sure to First convert Mills to see Mills and use K value for the aluminum the reference
18.69 ohms 17.7 × 10,560/10,000
you wish to use number 18 tungsten wire at 20 degrees C to make a 10 Ohm resistor. What length of wire will be required for this job. be sure to use K value in the reference
479.29 L= R × K / A 10×1,620 /33.8
find the cross-sectional area of a conductor in millimeters squared when the diameter of the conductor is 25 mm.pi must be calculated as 3.14159
490 .8734375 a=( d/2)^2×3.14159 =(25/2)^2×3.14159
what is the formula to find the cross-sectional area of a cable in square inches
A=(d/2)^2×3.14
and the United States conductors are sized according to the ? standard or by the actual number of circular mil for the wire
American wire gauge
what is the formula to find the line loss
Pixar.... oh shit my bad P=I^2×R
the cross-sectional area of a American conductor is expressed in units called
circular mils
electrical energy usage is measured and volt amps
false
the unit of measurement used by electric companies to determine a monthly electric bill is the?
kilowatt hour
explain how to calculate the approximate cross-sectional area of a conductor in circular mils
measure the diameter of the conductor in inches. Multiply the result by 1,000 then Square it
what is the approximate gauge of wire that has a diameter of about 100 Mills
number 10 AWG
what is the formula for calculating the resistance of wire
r = k×l /a R is resistance in ohms K is the constant based on the material L is the length A is the area in circular mils
different wattage ratings are achieve for lamps with the same voltage rating by changing the value of the?
resistance
specific resistance is also called? And is abbreviated with the capital letter K or the Greek letter p
resistivity
the resistance of a specified length of wire of a certain type is directly proportional to its? and inversely proportional to its cross-sectional area
specific resistance
why will a lamp with a 100 ohm filament burn brighter than a lamp with a 300 ohm filament
there's less resistance in the 100 on filament. Therefore more current will flow causing more Heating and incandescent action
The Unwanted heat generated by an incandescent lamp is considered a power loss
true
the higher the resistance the lower the rated wattage of a lamp
true
the measurement kilowatt-hour expresses how much energy is used over a. Of time
true
lamps have both a? Rating and a? Rating
voltage / power
which of the following is not a characteristic that determines the resistance of a conductor
voltage rating of the conductor