Find the force on a negative charge that is placed midway between two equal positive charges. All charges have the same magnitude.

The force on a negative charge that is placed midway between two equal positive charges is zero when all charges have the same magnitude.

Explanation:

Let us assume that

As is the negative charge and placed midway between two equal positive charges ( and ).

Total distance between and is 2r. This means that the distance between and , and = d = r

Now, force action on charge due to is as follows.

where,

k = electrostatic constant =

Substitute the values into above formula as follows.

... (1)

Similarly, force acting on due to is as follows.

  ... (2)

As both the forces represented in equation (1) and (2) are same and equal in magnitude. This means that the net force acting on charge is zero.

Thus, we can conclude that the force on a negative charge that is placed midway between two equal positive charges is zero when all charges have the same magnitude.

what experimental evidence led scientists to change from the previous model to this one?

a few of the positive particles aimed at a gold foil seemed to bounce back.

the colors of light emitted from heated atoms had very specific energies.

experiments with water vapor showed that elements combine in specific proportions.

cathode rays were bent in the same way whenever a magnet was brought near them.

im srry but ur wrong the answer is d a smooth rock, some red dirt, and an empty bird's nest.