Why do motors have gaps or breaks throughout the rotor and commutator? a) It makes the motor cheaper since not as much material is needed.
b) Only some sections of the rotor will act as electromagnets, causing the rotor too always be pushed in the same direction.
c) It allows some of the magnetic field to escape so that rotor doesn't get too stressed.
d) It lets air into the motor to keep it cool since the electricity can make it hot.
e) It happens when rotors don't use enough oil, so they crack.

Neptune is the eighth planet from the sun. it was the first planet to get its existence predicted by  mathematical calculations  before it was actually seen through a telescope on sept. 23, 1846. irregularities in the orbit of  uranus  led french astronomer alexis bouvard to suggest that the gravitational pull from another celestial body might be responsible. german astronomer johann galle then relied on subsequent calculations to   spot neptune via telescope. previously, astronomer galileo galilei sketched the planet, but he mistook it for a star due to its slow motion. in accordance with all the other planets seen in the sky, this new world was given a name from greek and roman mythology — neptune, the roman god of the sea.