Linear expansivity is the fractional increase in length of a specimen of a solid, per unit rise in temperature.
Answer:

Explanation:
Assuming this problem: "Part (a) of the figure attached shows a non-conducting rod with a uniformly distributed charge +Q. The rod forms a half circle with radius R and produces an electric field of magnitude Earc at its center of curvature P. If the arc is collapsed to a point at distance R from P (Figure b), by what factor is the magnitude of the electric field at P multiplied?"
On this case the charge density is given by this formula:
assuming a half circle
We can find the force acting on the x axis with this:


We can cnvert the integral using the symmetrical property:

And we can find the electric field like this:

And the electric field just by the charge is given by:

And if we find the ratio for the two electrical fields we got:

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<span>"In designing electrical circuits, it is important to know the characteristics of circuits in order to know how to solve related problems that will arise whenever there will be problems in the circuits made. For example, series circuits makes the other lights go off whenever one bulb does not work. It would be easier to determine how to fix it because we know what type of circuit it is."
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You should be able to use this and any other knowledge you know to come up with your desired answer
source:
brainly.com/question/1269647