Basic Electrical Principles Flashcards

What is the electrical resistance of a perfect conductor?

Answer: Zero ohms

A perfect conductor has zero resistance, allowing current to flow without any opposition or energy loss.

A 120-volt circuit draws 2 amperes of current. What is the power consumption?

Answer: 240 watts

Power (P) = Voltage (V) × Current (I) = 120 V × 2 A = 240 watts.

What happens to total resistance when resistors are added in parallel?

Answer: Total resistance decreases

Adding resistors in parallel creates more paths for current, which reduces the overall resistance of the circuit.

Which of the following is an example of an electrical insulator?

Answer: Plastic

Plastic has very high resistance and does not allow current to flow easily, making it a good insulator.

A battery's voltage represents which of the following?

Answer: The electrical pressure that pushes current through a circuit

Voltage (electromotive force) is the electrical pressure or potential difference that drives current through a circuit.

What is the relationship between watts, volts, and amps described by?

Answer: P = V × I

The power formula P = V × I (Power equals Voltage times Current) is fundamental to electrical calculations.

If a 12-volt battery is connected to a 4-ohm resistor, how much current flows?

Answer: 3 amperes

Using Ohm's Law: I = V/R = 12 V ÷ 4 Ω = 3 amperes.