You apply the brakes of your car abruptly and your book starts sliding off the front seat. three observers sitting in the car explain this differently. observer a says that the book continued moving and the car accelerated from underneath it. observer b says that the car pushed forward on the book. observer c says that she must be in a noninertial reference frame because the book started moving without any extra objects interacting with it. which of the observers is correct? assume that the car is a frame of reference of all observers.

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.