B. Objects A and C possess charges of opposite sign.
<h3>
Attraction of two objects</h3>
The attraction of two objects occurs when the two objects have opposite charges.
<h3>
Repulsion of two objects</h3>
The repulsion of two objects occurs when the two objects have same charges.
Thus, we can conclude that, objects A and C possess charges of opposite sign.
Learn more about attraction of charges here: brainly.com/question/16033085
#SPJ1
Answer:
![\frac{R_2}{R_1}=\frac{A_1}{A_2}\\\frac{R_4}{R_3}=\frac{A_3}{A_4}](https://tex.z-dn.net/?f=%5Cfrac%7BR_2%7D%7BR_1%7D%3D%5Cfrac%7BA_1%7D%7BA_2%7D%5C%5C%5Cfrac%7BR_4%7D%7BR_3%7D%3D%5Cfrac%7BA_3%7D%7BA_4%7D)
Explanation:
The resistance of a conductor is directly proportional to its length and is inversely proportional to its cross-sectional area, this dependence is given by:
![R=\frac{\rho L}{A}](https://tex.z-dn.net/?f=R%3D%5Cfrac%7B%5Crho%20L%7D%7BA%7D)
is the material's resistance, L is the legth and A is the cross-sectional area.
For the first and second coils, we have:
![R_1=\frac{\rho L}{A_1}\\R_2=\frac{\rho L}{A_2}\\\rho L=R_1A_1\\\rho L=R_2A_2\\R_1A_1=R_2A_2\\\frac{R_2}{R_1}=\frac{A_1}{A_2}](https://tex.z-dn.net/?f=R_1%3D%5Cfrac%7B%5Crho%20L%7D%7BA_1%7D%5C%5CR_2%3D%5Cfrac%7B%5Crho%20L%7D%7BA_2%7D%5C%5C%5Crho%20L%3DR_1A_1%5C%5C%5Crho%20L%3DR_2A_2%5C%5CR_1A_1%3DR_2A_2%5C%5C%5Cfrac%7BR_2%7D%7BR_1%7D%3D%5Cfrac%7BA_1%7D%7BA_2%7D)
For the third and fourth coils, we have:
![R_3=\frac{\rho L'}{A_3}\\R_4=\frac{\rho L'}{A_4}\\\rho L'=R_3A_3\\\rho L'=R_4A_4\\R_3A_3=R_4A_4\\\frac{R_4}{R_3}=\frac{A_3}{A_4}](https://tex.z-dn.net/?f=R_3%3D%5Cfrac%7B%5Crho%20L%27%7D%7BA_3%7D%5C%5CR_4%3D%5Cfrac%7B%5Crho%20L%27%7D%7BA_4%7D%5C%5C%5Crho%20L%27%3DR_3A_3%5C%5C%5Crho%20L%27%3DR_4A_4%5C%5CR_3A_3%3DR_4A_4%5C%5C%5Cfrac%7BR_4%7D%7BR_3%7D%3D%5Cfrac%7BA_3%7D%7BA_4%7D)
Twice the momentum as 5 doubled is 10 so it is B
Visible light or electromagnetic radiation within 400nm to 700nm is responsible for colour of the spectrum.
Explanation:
The electromagnetic spectrum contains radiations of varying wavelength. The radiations with the lowest energy are characterised by the longest wavelength.
Within this spectrum lies the visible light which enables us to see a different colour. The radiations within the range 400nm to 700nm are included in the visible spectrum.
While violet lies at the 400nm spectrum part red colour lies at 700nm part. As the wavelength of the radiation transverses between 400-700 nm, the colour of the object changes accordingly.