If you're referring to the different colors that usually occur at the tip of missles, rockets and some other aircraft, it either a) signifies the end of a particular plate of metal, fabricated specifically to be for the nose. Sometimes these can even be a different alloy or metal all together. or b) this shows where the curved surface begins, so in the case of damage or imperfections due to wear, they can be repaired and measured more easily. The shape of the nose is extremely important for smooth flight, and a dent or bump formed on it can make the aircraft unstable. If you can measure from where the curve starts by the difference in color, it makes repairing or re-fabricating the part much easier. Many of these curves aren't as simple as they appear.
<span>238,900 mi hope it helps :)</span>
The blank distance is your answer
There are two laws named for Kirchhoff. The both concern electrical circuits.
Here they are in my own words:
1). The sum of the voltage drops around any closed loop in a circuit is zero.
2). The sum of the currents at any single point in a circuit is zero.
it allows only a reduced number of electrons to flow through it.