4. How far apart are a proton and electron if they exert an attractive force of 3 N on one another?

For the force due to electromagnetism we use Coulomb’s inverse square law:

F=keq1q2r2

(where F is the electrostatic force, q1 & q2 are the two charges, r is the distance between them, and Coulomb’s Constant ke=14πϵ0=8.99×109Nm2C−2, where ϵ0 is the permittivity of free space)

r=keq1q2F−−−−−√

r=8.99×109Nm2C−2−1.60×10−19C×−1.60×10−19C1.0N−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−√

r=1.52×10−14m

Explanation:

the correct choice is a .

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beta is electron from nucleus

something from nucleus has changed, but charge must be same for cons of charge