The power used by an electric tool can be determined by multiplying the resistance times the current current times the voltage resistance times the voltage

Power can be expressed by the product of current and voltage.  To see this, consider the units of current and voltage:



Where C is coulombs (charge), s is seconds, J is joules (energy), and W is Watts, or power.  See that watts are Joules per second, or the time rate of change of energy.

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.