BMST - Basic Math and Science Electrical Circuits and Ohm's Law Questions and Answers — Questions and Answers
Question 1: Ohm's Law describes the fundamental relationship between which three electrical quantities?
- Power, Current, and Capacitance
- Voltage, Current, and Resistance (Correct answer)
- Charge, Time, and Inductance
- Resistance, Frequency, and Power
Correct answer: Voltage, Current, and Resistance
Ohm's Law is a foundational principle in electronics, stated as V = IR, where V is voltage, I is current, and R is resistance. This law defines the direct proportionality between voltage and current when resistance is constant.
Question 2: A simple circuit has a 24-volt power source and a single 8-ohm resistor. According to Ohm's Law, what is the current flowing through the circuit?
- 192 Amperes
- 0.33 Amperes
- 3 Amperes (Correct answer)
- 32 Amperes
Correct answer: 3 Amperes
Using Ohm's Law (V = IR), you can rearrange the formula to solve for current: I = V/R. Substituting the given values, I = 24 Volts / 8 Ohms, which equals 3 Amperes.
Question 3: If three resistors are connected end-to-end in a single path, this configuration is known as a series circuit. What is the total resistance of a series circuit containing a 5 Ω, a 10 Ω, and a 15 Ω resistor?
- 2.73 Ω
- 15 Ω
- 750 Ω
- 30 Ω (Correct answer)
Correct answer: 30 Ω
In a series circuit, the total resistance is the sum of the individual resistances. Therefore, R_total = R1 + R2 + R3 = 5 Ω + 10 Ω + 15 Ω = 30 Ω.
Question 4: Which of the following statements is a key characteristic of a simple parallel circuit?
- The current is the same through every component.
- The total resistance is the sum of the individual resistances.
- The voltage is the same across every component. (Correct answer)
- Removing one component will always break the entire circuit.
Correct answer: The voltage is the same across every component.
In a parallel circuit, all components are connected across the same two points, meaning the voltage across each parallel branch is identical. Current is divided among the branches, and total resistance is calculated using the reciprocal formula.
Question 5: In a circuit with a constant resistance, if the voltage is doubled, what is the resulting effect on the current?
- The current is halved.
- The current is doubled. (Correct answer)
- The current remains the same.
- The current is quadrupled.
Correct answer: The current is doubled.
According to Ohm's Law (I = V/R), current is directly proportional to voltage when resistance is constant. Therefore, if the voltage is doubled, the current will also double to maintain the relationship.
Question 6: What are the correct standard international (SI) units for electrical potential difference (voltage), electric current, and electrical resistance, respectively?
- Ampere, Ohm, Volt
- Watt, Ampere, Volt
- Volt, Ampere, Ohm (Correct answer)
- Ohm, Volt, Watt
Correct answer: Volt, Ampere, Ohm
The standard SI unit for voltage is the Volt (V), the unit for current is the Ampere (A), and the unit for resistance is the Ohm (Ω).
BMST - Basic Math and Science Electrical Circuits and Ohm's Law Questions and Answers
Ohm's Law describes the fundamental relationship between which three electrical quantities?