Two identical charges experience a repulsive force of magnitude 21 N when their separation is 1.6 m. What is the magnitude of each charge? k = 8.99 x 109Nm2/C2.
a. 3.41x10-50

b. 5.55x10-50

c. 2.45 10-50

d. 7.49x10-5C

An  atom  (ours, not carroll's) consists of a positively charged  nucleus, surrounded by one or more negatively charged particles called  electrons. the positive charges equal the negative charges, so the atom has no overall charge; it is electrically neutral. most of an atom's mass is in its nucleus; the mass of an electron is only 1/1836 the mass of the lightest nucleus, that of hydrogen. although the nucleus is heavy, it is quite small compared with the overall size of an atom. the radius of a typical atom is around 0.1 to 0.25 nanometres (nm), whereas the radius of a nucleus is about 10-6  nm.  *  if an atom were enlarged to the size of the earth, its nucleus would be only 200 feet in diameter and could easily rest inside a small football stadium.read more on -

Sorry my friend i don't know the answer. i am just in 6th