How much force does it take to stop a 1,000 kg car traveling at 20 m/s in 10 seconds?

The initial momentum of the car is

                (mass) x (speed)  =  20,000 kg-m/s

"Impulse" is (force exerted) x (time the force lasts)
and it's equal to the change in momentum.

              (Force) x (10 sec)  =  20,000 kg-m/s

Divide each side by  (10 sec)  and you have

                      Force  =  (20,000 kg-m/s) / (10 sec)

                                 =          2,000 kg-m/s²  =  2,000 Newtons

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 -