There are certain formulas in physics that are so powerful and so pervasive that they reach the state of popular knowledge. The predominant equation which pervades the study of electric circuits is often referred to as the Ohm's law...

Review the components of a circuit and their symbols such as battery, resistor, and switch. Analyze how the power of a resistor is related to the current and electric potential difference across the resistor.

One-page profile of influential innovator, George Westinghouse, Jr., whose vision and ideas helped to increase the safety of the railroad system in America. His experimentation with electricity also had a huge impact on the power...