Basic DC Fundamentals 1

The flow of electricity in a circuit is based on the flow of electrons. Electrons are negatively charged particles that carry the electric current. When a voltage is applied to a circuit, electrons move from the negative terminal of the power source to the positive terminal, creating a flow of electricity. Neutrons, quarks, atoms, and nuclei do not carry an electric charge or participate in the flow of electricity in a circuit.

The basic measurement of resistance is Ohm. Ohm is the unit of electrical resistance, representing the amount of opposition to the flow of electric current in a circuit. It is named after the German physicist Georg Simon Ohm, who first formulated Ohm's law relating current, voltage, and resistance. The Ohm is commonly used in electrical and electronic circuits to measure and express the resistance of various components and materials.

A diode is a semiconductor device that allows current to flow in only one direction. It has a p-n junction, which acts as a one-way valve for electrical current. When a positive voltage is applied to the anode (positive terminal) and a negative voltage to the cathode (negative terminal), the diode conducts current. However, if the polarity is reversed, the diode blocks the flow of current. Therefore, the correct answer is "one direction" as current flows through a diode in only one direction.

Power is a measure of the rate at which work is done or energy is transferred. It is expressed in watts, which is the unit of power. Watts represent the amount of energy transferred or work done per unit time. Therefore, power is the correct answer as it is the appropriate unit for expressing power. Volts, amps, and ohms are units of voltage, current, and resistance respectively, which are not directly related to power.

Complex circuits can be simplified using Kirchoff's laws. Kirchoff's laws are fundamental principles in circuit analysis that allow us to analyze and solve complex circuits. These laws, namely Kirchoff's current law and Kirchoff's voltage law, provide a systematic approach to understanding the behavior of currents and voltages in a circuit. By applying these laws, we can simplify complex circuits into simpler equivalent circuits, making it easier to analyze and calculate various circuit parameters. Newton's, Faraday's, Franklin's, and Brewster's laws are not directly related to circuit analysis and cannot be used to simplify complex circuits.

In a series circuit, the current is always the same throughout the circuit. This is because in a series circuit, the current has only one path to flow through, and it encounters the same amount of resistance at every point. Therefore, the current remains constant throughout the circuit.

Ohm's law states that the voltage (E) across a conductor is equal to the current (I) flowing through it multiplied by the resistance (R) of the conductor. Therefore, the correct answer, E=I*R, represents the relationship between voltage, current, and resistance as stated by Ohm's law.

Horsepower is a unit of power that measures the rate at which work is done. It is commonly used to measure the power output of engines and motors. Watts, on the other hand, is also a unit of power that measures the rate of energy transfer or conversion. Since both horsepower and watts are units of power, it is correct to say that horsepower is measured in watts.

Resistors are rated in watts because watts measure the rate at which electrical energy is consumed or dissipated. In the case of resistors, the wattage rating indicates the amount of power the resistor can handle without getting damaged. It is important to choose a resistor with the correct wattage rating to ensure it can handle the power flowing through it without overheating or failing.