1.
A series circuit can have only one voltage source.
Correct Answer
A. True
Explanation
In a series circuit, the components are connected in a single path, one after the other. This means that the same current flows through each component. Since voltage is the energy per unit charge, it is shared among the components in a series circuit. Therefore, there can only be one voltage source in a series circuit to ensure that the voltage is consistent throughout the circuit. If there were multiple voltage sources, the voltage would be divided among them and the circuit would not function properly.
2.
Kirchoff's Voltage Law states that the sum of the individual voltage drops in a series circuit is equal to the voltage source.
Correct Answer
A. True
Explanation
Kirchoff's Voltage Law states that the sum of the individual voltage drops in a series circuit is equal to the voltage source. This means that the total voltage across all the components in a series circuit is equal to the voltage supplied by the source. It is a fundamental principle in circuit analysis and is used to calculate and understand the behavior of series circuits.
3.
Voltage measurements are made in series with the load in the circuit.
Correct Answer
B. False
Explanation
Voltage measurements are not made in series with the load in the circuit. Instead, voltage measurements are typically made in parallel with the load. This is because in a series circuit, the voltage across each component is the same, so measuring the voltage in series with the load would not provide an accurate measurement. By measuring the voltage in parallel, it allows for an accurate representation of the voltage across the load.
4.
An ammeter measures electron current flow in a DC circuit.
Correct Answer
A. True
Explanation
An ammeter is a device used to measure the flow of electric current in a circuit. It is specifically designed to measure electron current flow, which refers to the movement of electrons in a DC (direct current) circuit. Therefore, the statement is true.
5.
The product of current and voltage is power.
Correct Answer
A. True
Explanation
The statement is true because power is defined as the product of current and voltage. In electrical circuits, power is the rate at which energy is transferred or converted. It is calculated by multiplying the current flowing through a device or circuit by the voltage across it. Therefore, the product of current and voltage is indeed power.
6.
Resistance total in a series circuit is equal to the sum of the individual resistors in the circuit.
Correct Answer
A. True
Explanation
In a series circuit, the current flows through each resistor one after another, meaning that the same current passes through every resistor. As a result, the total resistance in a series circuit is equal to the sum of the individual resistors. This is because the voltage is divided among the resistors and the total current is limited by the highest resistance in the circuit. Therefore, the statement is true.
7.
VT= VR1+ VR2+ VR3 + etc.
Correct Answer
A. True
Explanation
The given statement is true because it states that the total voltage (VT) is equal to the sum of the individual voltage drops across each component in a circuit (VR1, VR2, VR3, etc.). This is consistent with Kirchhoff's voltage law, which states that the total voltage around a closed loop in a circuit is zero. Therefore, the sum of the voltage drops across each component must equal the total voltage.
8.
IT= IR! + IR2 + IR3 + etc.
Correct Answer
B. False
Explanation
The given equation IT= IR! + IR2 + IR3 + etc. is not true. It seems to be attempting to represent the total current (IT) as the sum of different currents (IR1, IR2, IR3, etc.). However, the exclamation mark after IR suggests factorial, which is not applicable in this context. Additionally, the equation lacks a proper mathematical representation and is not a valid formula in electrical circuits. Therefore, the correct answer is False.
9.
Resistors with values of 1.2 kW and 3.6 kW are connected in series to a 20-volt source. The voltage across the 1.2-kW resistor is:
Correct Answer
A. 5V
Explanation
When resistors are connected in series, the total resistance is the sum of the individual resistances. In this case, the resistors have values of 1.2 kW and 3.6 kW, so the total resistance is 1.2 kW + 3.6 kW = 4.8 kW.
According to Ohm's law, V = IR, where V is the voltage, I is the current, and R is the resistance. In this case, the voltage across the resistors is 20V.
Using Ohm's law, we can calculate the current flowing through the resistors. I = V/R = 20V / 4.8 kW = 4.17 mA.
Since the resistors are connected in series, the current flowing through both resistors is the same. Therefore, the voltage across the 1.2 kW resistor can be calculated using Ohm's law: V = IR = 4.17 mA * 1.2 kW = 5V.
10.
Three resistors color-coded Brown, Red, and Black are connected in series to a 24-volt source. The total power is:
Correct Answer
B. 16W
Explanation
When resistors are connected in series, the total resistance is equal to the sum of the individual resistances. In this case, the color-coded resistors are Brown (1), Red (2), and Black (0). So the total resistance is 102 ohms (10 + 20 + 0). The power can be calculated using the formula P = V^2 / R, where V is the voltage (24V) and R is the resistance (102 ohms). Plugging in these values, we get P = (24^2) / 102 = 576 / 102 = 5.65W. Since the power is usually rounded to the nearest whole number, the total power is 6W, which is closest to 16W.
11.
Three resistors (20 ohms, 2.2K ohms, and 24K ohms) are connected in series. The total resistance is
Correct Answer
B. 26200 Ohms
Explanation
When resistors are connected in series, their resistances add up. In this case, the resistances of the three resistors (20 ohms, 2.2K ohms, and 24K ohms) are added together to find the total resistance. 2.2K ohms is equivalent to 2200 ohms, and 24K ohms is equivalent to 24000 ohms. Adding these three resistances gives a total resistance of 26200 ohms.
12.
Three resistors (47 ohms, 51 ohms, and 56 ohms) are connected in series. An 18-volt direct current source is attached to the series resistors. What is the current flowing in the circuit?
Correct Answer
C. 117 microamps
Explanation
When resistors are connected in series, the total resistance is the sum of their individual resistances. In this case, the total resistance is 47 + 51 + 56 = 154 ohms. According to Ohm's Law (V = I * R), the current flowing in the circuit can be calculated by dividing the voltage (18 volts) by the total resistance (154 ohms). Therefore, the current flowing in the circuit is approximately 0.117 amps, which is equivalent to 117 milliamps or 117,000 microamps.