An impeller (also written as impellor or impellar) is a rotor used to increase (or decrease in case of turbines) the pressure and flow of a fluid. An impeller for a dam turbine generator.
The smallest planet in the Solar System is Mercury (the biggest planet is Jupiter). For the longest time, the smallest planet was considered to be Pluto, but now Pluto isnât a planet any more, so weâre back to Mercury.Mercury measures 4879 km along its equator.Just for comparison, Earth is 12,742 km across.So Mercury is only 38% the diameter of Earth.or the longest time, the smallest planet was considered to be Pluto, but now Pluto isnât a planet any more, so weâre back to Mercury. Mercury measures 4879 km along its equator. Just for comparison, Earth is 12,742 km across.
According to the classification based on size, Pluto is one of the small planets. The other four small planets are Mercury, Venus, Earth and Mars. These planets all have diameters less than 13000 kilometers. The other four planets, Jupiter, Saturn, Uranus and Neptune are known as the giant planets or the gas giants. These planets have diameters greater than 48000 kilometers.