If you slice a wire cleanly and then look at the cut end, you see a little circle at the end.
The area of that circle is the "cross-sectional area" of the wire. The larger that area is,
the lower the DC resistance of the wire is.
When it is on the cross-sectional area it is inversely proportional to the wire,otherwise it is directly proportional to the wire.
The resistance is based on the cross sectional area. It is conceivable that you could bend a wire in such a way as to affect the cross sectional area, but unlikely.
3 is the number of conductors and 29 is wire gauge(either in diameter or cross sectional area)
the resistance can never increase or decrease....... (you can't open the resistor and take out the something and make the resistance increase or decrease)AnswerSince resistance is directly proportional to the length of a conductor, increasing the length of a wire will increase its resistance. For example, if you double its length, you will double its resistance.
Assume that the increase in length is achieved by uniform reduction in the cross-sectional area of the wire. Then an increase in length by 4 times will result in the cross sectional area being reduced to a fifth of it original value. This will increase the resistance to five times its previous value.
When it is on the cross-sectional area it is inversely proportional to the wire,otherwise it is directly proportional to the wire.
The resistance is based on the cross sectional area. It is conceivable that you could bend a wire in such a way as to affect the cross sectional area, but unlikely.
If the diameter doubles (x2), the cross-sectional area quadruples (x4).
Imagine the wire is straight, now cut through at right angle to the centre line, the exposed surface is the cross sectional area, on a round wire it = pi * radius2 (area of a circle)
Other things being equal, more cross-sectional area will cause less resistance.
Since resistance is inversely-proportional to cross sectional area, the lower the cross-sectional area, the higher the resistance. So ALL types of wire exhibit this behaviour!
It quadruples.
0.0031
Temperature, Length of wire, Area of the cross-section of wire and nature of the material.
Assuming the wire follows Ohm's Law, the resistance of a wire is directly proportional to its length therefore doubling the length will double the resistance of the wire. However when the length of the wire is doubled, its cross-sectional area is halved. ( I'm assuming the volume of the wire remains constant and of course that the wire is a cylinder.) As resistance is inversely proportional to the cross-sectional area, halving the area leads to doubling the resistance. The combined effect of doubling the length and halving the cross-sectional area is that the original resistance of the wire has been quadrupled.
Resistance is inversely-proportional to the cross-sectional area of a conductor. For example, doubling its cross-sectional area will halve its resistance, while halving its cross-sectional area will double its resistance.Since the cross-sectional area of a circular-section conductor is proportional to the square of its radius, doubling that radius will reduce its resistance by one quarter, while halving its radius will quadruple its resistance.
The gauge of a wire measures its cross-sectional area and helps determine its current carrying capacity.