Limits of expressions involving the trigonometric functions can be evaluated by direct substitution --- unless division by zero is encountered. When division by zero is encountered, simplifications such as the ones presented in the Conceptual Understanding of Limits lesson can be attempted.
A short circuit is an abnormal connection between two nodes of an electric circuit intended to be at different voltages. This results in an excessive electric current limited only by the Thevenin thÃ©venin equivalent resistance of the rest of the network and potentially causes circuit, damage, overheating fire or. explosion
And yet, power just means energy flow per unit time. We all know the Watt is a unit of power consumption and have an idea how quickly a 1500 Watt kettle boils water. The unit of energy is the Joule - a Watt is just a flow of one Joule per second. The other popular unit of power is the horsepower. The conversion is that one horsepower = 756 Watts. A 100-HP car would be able to turn a 75,600 - Watt electrical generator, or 75.6 kilowatts. So anybody who does talk about energy, rarely speaks in Joules.