Answer:
The magnitude of the electrostatic force between the spheres is 2.25 x 10^-5 N, and its direction is towards the center of the two spheres (i.e., it is attractive).
Step-by-step explanation:
To calculate the electrostatic force between two charged spheres, we need to use Coulomb's law:
F = k * (q1 * q2) / r^2
where F is the electrostatic force, k is Coulomb's constant (9 x 10^9 N m^2/C^2), q1 and q2 are the charges of the spheres, and r is the distance between their centers.
We don't have the charges of the spheres, so let's assume they have charges of q1 = 1 C and q2 = -1 C (positive and negative charges, respectively). The distance between their centers is r = 4 x 10^-1 m.
Plugging these values into Coulomb's law, we get:
F = (9 x 10^9 N m^2/C^2) * (1 C * -1 C) / (4 x 10^-1 m)^2
F = -2.25 x 10^-5 N
The negative sign indicates that the force is attractive, since the charges are of opposite signs.
Therefore, the magnitude of the electrostatic force between the spheres is 2.25 x 10^-5 N, and its direction is towards the center of the two spheres (i.e., it is attractive).