Which statement is true? speed is a scalar quantity and velocity is a vector quantity. speed and velocity are both scalar quantities. speed and velocity are both vector quantities. speed is a vector quantity and velocity is a scalar quantity. speed and velocity are neither a scalar quantity nor a vector quantity.

The density of a liquid could be found by using

Acoal-fired plant generates 600 mw of electric power. the plant uses 4.8 x 10^6 kg of coal each day, and the heat of combustion of coal is 3.3x 10^7 j/kg. the steam that drives the turbines is at a temperature of 300° c, and the exhaust water is at 37° c. (a) what is the overall efficiency of the plant for generating electric power? (b) how much thermal energy is exhausted each day? (c) what is the change in entropy of the universe for this heat engine? (d) using the same heat reservoirs, what is the maximum possible (carnot) efficiency for a heat engine?

If y gets smaller as x gets bigger and y have an relationship?