Two iron spheres are suspended from strings and
separated by a distance of 9.0 meters. The
charge on one sphere is 7.0*10^-8 Cand the other -3.0
*10^-5 C. What is the electric force on the spheres?
A. A repulsive force of 4.6*10^-4N
B. An attractive force of 2.3*10^-4 N
C. An attractive force of 4.6*10^-4 N
D. A repulsive force of 2.3*10^-4 N

B. An attractive force of 2.3*10^-4 N

Explanation:

As we know by Coulomb's law that the electrostatic force between two charges is given as

here we know that

r = 9.0 m

now we have

since both charges are opposite charges so they will attract each other by the force we calculated above so correct answer will be

B. An attractive force of 2.3*10^-4 N

wavelegth as in spectrum red oygbiv

answer: the metamorphic rocks are formed when they are exposed to high pressure and high temperatures. this happens when one of the earth's plates comes in contact with the other plate by traveling in opposite directions, straight into each other or slipping under one another. the friction that is caused by this activity results in   melting of rocks and when it cools they are known as metamorphic rocks. this process needs a controlled amount of pressure and temperature otherwise it may turn into magma.