The basic components of analog circuits are wires, resistors, capacitors, inductors, diodes, and transistors. Analog circuits are very commonly represented in schematic diagrams, in which wires are shown as lines, and each component has a unique symbol.

Every circuit is comprised of three major components:

• a conductive “path,” such as wire, or printed etches on a circuit board;
• a “source” of electrical power, such as a battery or household wall outlet, and,
• a “load” that needs electrical power to operate, such as a lamp.

Most circuits have at least four things in common: power source, conductor, electrical device, and object that use the electricity.

In a series circuit, every device must function for the circuit to be complete. One bulb burning out in a series circuit breaks the circuit. In parallel circuits, each light has its own circuit, so all but one light could be burned out, and the last one will still function.

Increasing the number of bulbs in a series circuit decreases the brightness of the bulbs. Bulbs in parallel are brighter than bulbs in series. In a parallel circuit the voltage for each bulb is the same as the voltage in the circuit.

What happens if one device in a parallel circuit fails? A break in any one path does not interrupt the flow of current in the other paths. The reciprocal of the total resistance is equal to the sum of the reciprocals of individual resistance.

The disadvantage of a parallel connection becomes apparent with a short circuit, such as when someone jams a wire between the two contacts of an electrical outlet. A short circuit has very low resistance, which in turn causes current in the circuit to increase tremendously, and bang!

When a resistor breaks down, current typically flows through the burnt resistor without any resistance and thereby passes unchecked. Other components in the circuit may become damaged from the excess current flowing through.

When resistors are connected in parallel, more current flows from the source than would flow for any of them individually, so the total resistance is lower. Each resistor in parallel has the same full voltage of the source applied to it, but divide the total current amongst them.

The trick is to look at the nodes in the circuit. A node is a junction in the circuit. Two resistor are in parallel if the nodes at both ends of the resistors are the same. If only one node is the same, they are in series.

Two or more resistors are said to be connected in parallel, if the same potential difference exist across them.

8. Which is the most cost efficient connection? Explanation: The advantage of series-connections is that they share the supply voltage, hence cheap low voltage appliances may be used.

What becomes the Voltage if we use 2 resistors of 4W in parallel? As any other data is not provided, the voltage across two resistors of 4w in parallel is the same.

In a parallel circuit, the voltage drops across each of the branches is the same as the voltage gain in the battery. Thus, the voltage drop is the same across each of these resistors. The voltage at each end of a wire is the same (ideally), So all the components have to have the same voltage.

Resistors are in parallel when they are connected between the same two nodes. It follows that resistors in parallel have the same voltage across their respective terminals.

The voltage across each of the components in series is in the same proportion as their resistance : if two identical components are connected in series, the supply voltage divides equally across them.

Current: The amount of current is the same through any component in a series circuit. Resistance: The total resistance of any series circuit is equal to the sum of the individual resistances. Voltage: The supply voltage in a series circuit is equal to the sum of the individual voltage drops.

Another way of saying this is that all components are connected across each other’s terminals. From this definition, three rules of parallel circuits follow: all components share the same voltage; resistances diminish to equal a smaller, total resistance; and branch currents add to equal a larger, total current.

A Parallel circuit has certain characteristics and basic rules:

• A parallel circuit has two or more paths for current to flow through.
• Voltage is the same across each component of the parallel circuit.
• The sum of the currents through each path is equal to the total current that flows from the source.

Rules regarding Series and Parallel Circuits

• Voltage drops add to equal total voltage.
• All components share the same (equal) current.
• Resistances add to equal total resistance.

Voltage applied to a series circuit is equal to the sum of the individual voltage drops. The voltage drop across a resistor in a series circuit is directly proportional to the size of the resistor. If the circuit is broken at any point, no current will flow.

The supply voltage is shared between components in a series circuit. The sum of the voltages across components in series is equal to the voltage of the supply. This means that if two identical components are connected in series, the supply voltage divides equally across them.

The current does not vary as it passes through each individual resistor. 2. In a series circuit the current is the same at any particular point on the circuit. The voltage in a series circuit, however, does not remain constant.

We’ve organized these principles into three basic rules:

• Rule 1 – Electricity will always want to flow from a higher voltage to a lower voltage.
• Rule 2 – Electricity always has work that needs to be done.
• Rule 3 – Electricity always needs a path to travel.