b. describes it best because a form of molten cools down and makes igneous rock. Good luck! Please mark me brainliest!
Answer:
Option C is the untrue statement.
We have that the electric field at the center of the metal ball due only to the charges on the surface of the metal ball is

From the question we are told that
A solid metal ball of radius 1.5 cm
bearing a charge of -15 nC is located near a hollow plastic ball of radius 1.9 cm bearing
uniformly distributed charge of -7 nC
The distance between the centers of the balls is 9 cm
Generally the equation for the electric field is mathematically given as


For more information on this visit
brainly.com/question/21811998
To solve this problem it is necessary to apply the concepts related to the magnetic field.
According to the information, the magnetic field INSIDE the plates is,

Where,
Permeability constant
Electromotive force
r = Radius
From this deduction we can verify that the distance is proportional to the field

Then the distance relationship would be given by




On the outside, however, it is defined by

Here the magnetic field is inversely proportional to the distance, that is

Then,



