1.
What is the basic unit of current?
Correct Answer
C. Amps
Explanation
The basic unit of current is amps, which is short for amperes. Current refers to the flow of electric charge in a circuit, and it is measured in amperes. Volts, watts, and joules are not units of current. Volts measure electrical potential difference, watts measure power, and joules measure energy. Therefore, the correct answer is amps.
2.
The flow of electricity through the circuit is known as what?
Correct Answer
A. Current
Explanation
The flow of electricity through a circuit is known as current. Current is the movement of electric charge carriers, such as electrons, through a conductor. It is measured in amperes (A) and is responsible for powering electrical devices and creating magnetic fields. Voltage refers to the electrical potential difference that drives the current, while resistance is the opposition to the flow of current in a circuit. "None of the above" is not the correct answer as current accurately describes the flow of electricity.
3.
A resistor consumes about 5 Watts, and a current of 5 Amperes flows through it. What is its voltage?
Correct Answer
D. 5 V
Explanation
The resistor consumes 5 Watts of power, and a current of 5 Amperes flows through it. To find the voltage, we use Ohm's Law. First, we determine the resistance (R) using the formula P = V * I, where P is power, V is voltage, and I is current. Solving for R, we find it to be 1 Ohm. Using Ohm's Law (V = I * R), the voltage across the resistor is then calculated as 5 Volts.
4.
Which of the following formula gives voltage?
Correct Answer
D. V=I*R
Explanation
The formula that gives voltage is:
V = I * R
Where:
V represents voltage in volts (V).
I represents current in amperes (A).
R represents resistance in ohms (Ω).
This formula is known as Ohm's Law, and it relates voltage, current, and resistance in an electrical circuit.
5.
What slows down the flow of current in a circuit?
Correct Answer
D. Resistance
Explanation
Resistance is the correct answer because it is a property of a material that opposes the flow of electric current. It is caused by collisions between electrons and atoms in the material, which generates heat and reduces the flow of current. The higher the resistance, the slower the flow of current in a circuit. Conductance, voltage, and current do not slow down the flow of current, but rather affect its magnitude or direction.
6.
Which of the following law are used to find the performance in a circuit?
Correct Answer
A. Ohm’s law
Explanation
Ohm's law is used to find the performance in a circuit. It states that the current flowing through a conductor is directly proportional to the voltage applied across it and inversely proportional to the resistance of the conductor. This law is commonly used to calculate the current, voltage, and resistance in a circuit, which helps in analyzing the performance and behavior of electrical circuits.
7.
What is a kilowatt?
Correct Answer
D. 1000 watts
Explanation
A kilowatt is a unit of power that measures the rate at which energy is used or transferred. It is equal to 1000 watts. Watts are a standard unit of power in the International System of Units (SI), and they represent the amount of energy transferred or used per second. Therefore, the correct answer is 1000 watts, as it accurately defines a kilowatt as a measurement of power.
8.
What does a switch do in a circuit?
Correct Answer
B. It turns off and on the flow through the circuit
Explanation
A switch in a circuit is used to control the flow of current. It can be used to turn the circuit on or off, allowing or interrupting the flow of electricity. By toggling the switch, the circuit can be energized or de-energized, controlling the operation of devices connected to the circuit. Therefore, the correct answer is "It turns off and on the flow through the circuit."
9.
A resistor has 3 volts across it. The resistance of the circuit is 1.5 ohms. What is the current of the circuit?
Correct Answer
B. 2A
Explanation
According to Ohm's Law, the current in a circuit can be calculated by dividing the voltage across the circuit by the resistance. In this case, the voltage across the circuit is 3 volts and the resistance is 1.5 ohms. Therefore, the current of the circuit can be calculated as 3 volts divided by 1.5 ohms, which equals 2A.
10.
A 1-ohm resistor has 5 volts of DC current across its terminals. What are the current (I) and the power consumed by the circuit?
Correct Answer
C. I = 5A & P = 5W
Explanation
The correct answer is I = 5A & P = 5W because according to Ohm's Law, the current (I) in a circuit is equal to the voltage (V) across the circuit divided by the resistance (R). In this case, the voltage is 5 volts and the resistance is 1 ohm, so the current is 5A. The power (P) consumed by a circuit can be calculated using the formula P = IV, where I is the current and V is the voltage. Substituting the values, we get P = 5A * 5V = 25W. Therefore, the power consumed by the circuit is 5W.