Electronics: Circuits and Schematics Flashcards

In a series circuit with three resistors of 10 ohms, 20 ohms, and 30 ohms, what is the total resistance?

Answer: 60 ohms

In a series circuit, total resistance is the sum of all individual resistances. Therefore, 10 + 20 + 30 = 60 ohms.

What does a dashed line represent on a standard electrical schematic?

Answer: A mechanical linkage or connection between components

On electrical schematics, dashed lines typically represent mechanical linkages or connections between components, such as ganged switches or mechanically coupled variable resistors, rather than electrical connections.

According to Kirchhoff's Current Law, what happens at a junction in an electrical circuit?

Answer: The sum of currents entering the junction equals the sum of currents leaving it

Kirchhoff's Current Law (KCL) states that the total current entering a junction must equal the total current leaving it. This is based on the conservation of electric charge.

On a schematic diagram, what does a zigzag line symbol typically represent?

Answer: A resistor

In standard electrical schematics (particularly US conventions), a zigzag line represents a resistor. This is one of the most commonly encountered symbols in circuit diagrams.

What is the total resistance of two 100-ohm resistors connected in parallel?

Answer: 50 ohms

For two equal resistors in parallel, the total resistance is half the value of one resistor. Using the formula 1/R_total = 1/R1 + 1/R2: 1/R_total = 1/100 + 1/100 = 2/100, so R_total = 50 ohms.

What is the purpose of a fuse in an electrical circuit?

Answer: To protect the circuit by melting and opening the circuit when current exceeds a safe level

A fuse contains a thin wire or metal strip that melts when excessive current flows through it, breaking the circuit and protecting wiring and components from damage due to overcurrent or short circuits.