DC Series circuits explained - The basics working principle

DC series circuits connect components end to end, allowing electrons to flow through each component in a single path. This setup is fundamental for understanding electrical circuits and differs from parallel connections where multiple paths exist. The video emphasizes the distinction between electron flow (negative to positive) and conventional current (positive to negative), noting that while both are taught, electron flow represents actual movement of charge.

Resistance in series circuits opposes the applied voltage and is measured in ohms. The total resistance is calculated by simply adding the resistances of each component, labeled as R1, R2, etc., with the total represented as RT. For example, a circuit with one resistor at 10 ohms has a total resistance of 10 ohms; adding another resistor at 5 ohms increases it to 15 ohms. Adding yet another five-ohm resistor brings it to a total of 20 ohms. While wires also contribute some resistance, it's usually negligible unless precision design is required.

Current, measured in Amperes (amps), represents the flow of electrons similar to water flowing through a pipe. To measure current, an ammeter or multimeter is placed within the circuit; this allows for accurate readings as long as the device is part of the electron flow path. The total current can be calculated by dividing voltage by resistance—adding more resistors increases resistance and decreases current, which reduces work output in circuits like LED setups where higher resistance results in dimmer lights. In series circuits, it's crucial to note that current remains constant throughout; regardless of measurement point or resistor arrangement, all electrons travel together along a single pathway.

Understanding Voltage Variation in Series Circuits In a series circuit, voltage varies while current remains constant. Voltage acts as the driving force for electrons, similar to water pressure in pipes; higher voltage allows more electron flow. Measuring voltage involves assessing the potential difference between two points—only differences can be measured across components like resistors. When multiple batteries are connected in series or when adding resistors of different values, total and individual voltages change accordingly due to resistance affecting how much energy is available at each point.

Calculating Voltage Drops Across Resistors Resistors create a path that reduces electron energy through collisions converting electrical energy into heat—a phenomenon known as voltage drop. The overall voltage drop equals the sum of all individual drops calculated by multiplying current with resistance values throughout the circuit. For example, using Ohm's law (V=IR), one can determine specific drops across various resistor configurations within circuits maintaining consistent currents but differing voltages based on their arrangement and value.

Power consumption in circuits can be calculated using two main equations: power (in watts) equals voltage squared divided by resistance, or power equals voltage multiplied by current. Resistors consume power as they create a voltage drop, converting electrical energy into heat. For example, with 10 ohms of resistance and a 9-volt battery providing 0.9 amps of current, the circuit consumes 8.1 watts—calculated either way yields the same result.

An LED has a maximum current limit of 0.02 amps (20 milliamps) to prevent burnout. When connected to resistors and a nine-volt battery, the approximate current in the circuit can be calculated based on these parameters. For further learning, viewers are encouraged to explore additional resources linked in the video description.