Aspring scale hung from the ceiling stretches by 5.6 cm when a 2.0 kg mass is hung from it. the 2.0 kg mass is removed and replaced with a 2.7 kg mass. what is the stretch of the spring

When the mass of 2.0 kg is attached to the spring, the force applied to the spring is the weight of the mass, so

This force stretches the spring by , so we can use Hook's law to find the spring constant:


Then the mass of 2.0 kg is removed and replaced with another mass m2=2.7 kg. The force produced by this mass is equal to its weight:

And so, we can use again Hook's law to calculate the new stretch of the spring:

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 -

The answer is d) by requesting advice on science internet sites