In a power plant, pipes transporting superheated vapor are very common. superheated vapor flows at a rate of 0.3 kg/s inside a pipe that is of diameter 5 cm and length10 m. the pipe is located in a power plant at a temperature of 25.5°c, and has a uniform pipe surface temperature of 100°c. if the temperature drop between the inlet and exit of the pipe is 30°c and the specific heat of the vapor is 2190 j/kg·k, determine the heat transfer coefficient as a result of convection between the pipe surface and the surroundings.

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 -

An atom's smaller negative particles are at a distance from the central positive particles, so the negative particles are easier to move. 

D. the index of refraction of the second medium is lower.