The formula is P3A X 110V 330 W with P standing for power. Power by definition is the rate of work or energy flow which are numerically the same. Watts are basically the miles-per-hour measurement of the electrical world--they tell you how fast the electrons are speeding down the highway.
The formula is W V A.
The dimension of power is energy divided by time. Watts Active power P or watts this is the value to be found. W V x I or W I 2 x R or W V 2 R. Power is usually abbreviated by W and measured in Watts.