📄 9th Grade Other: Alternating Current Concepts: Cycle, Period, Frequency, Capacitors, Inductors, Power, and Work Worksheet
📌 1. True / False
1. Alternating Current (AC) flows in only one direction.
2. The period of an AC waveform is the time it takes for one complete cycle.
3. A capacitor stores energy in a magnetic field.
4. Frequency is measured in Hertz (Hz).
5. Work is the rate at which energy is transferred or used.
✏️ 2. Fill in the Blanks
1. The number of complete cycles of an alternating current that occur in one second is called its .
2. An is an electrical component that stores energy in an electric field.
3. The unit for electrical power is the .
4. An is an electrical component that resists changes in current flow.
5. In AC circuits, electrical is done when charge is moved against an electric potential difference.
🔗 3. Matching
« One complete oscillation or repetition of an AC waveform.
« The time required to complete one full cycle of an AC waveform.
« The number of cycles per second, measured in Hertz.
« A device that stores electrical energy in an electric field.
« A device that stores energy in a magnetic field when current flows through it.
✍️ 4. Short Answer Questions
1. Briefly explain the main difference between Alternating Current (AC) and Direct Current (DC).
💡 Suggested Answer: Alternating Current (AC) periodically reverses its direction of flow, while Direct Current (DC) flows in only one constant direction.
2. What is the relationship between period (T) and frequency (f) in an AC circuit?
💡 Suggested Answer: The period (T) and frequency (f) are inversely related. This means that \( T = 1/f \) or \( f = 1/T \).
🎯 5. Multiple Choice
1. Which of the following components stores electrical energy in an electric field?
2. If an AC waveform completes 60 cycles in one second, what is its frequency?
3. The rate at which work is done or energy is transferred in an electrical circuit is defined as:
📝 6. Open-Ended Questions
1. An alternating current has a frequency of 50 Hz. Calculate its period.
💡 Solution Steps:
To calculate the period (T) from the frequency (f), we use the formula: \( T = 1/f \).
Given frequency \( f = 50 \text{ Hz} \).
Substitute the value into the formula:
\( T = 1/50 \text{ Hz} \)
\( T = 0.02 \text{ seconds} \).
Therefore, the period of the alternating current is 0.02 seconds.
2. Describe the primary function of an inductor in an AC circuit.
💡 Solution Steps:
An inductor is an electrical component typically made of a coil of wire. Its primary function in an AC circuit is to store energy in a magnetic field when current flows through it. More importantly, it opposes changes in the current flowing through it. When the current tries to increase, the inductor creates a magnetic field that resists this change. When the current tries to decrease, the inductor's magnetic field collapses, inducing a voltage that tries to maintain the current. This property is known as inductance.
3. If an electrical device consumes 1000 Joules of energy over a period of 10 seconds, calculate the average power consumed by the device.
💡 Solution Steps:
To calculate the average power (P), we use the formula: \( P = W/t \), where \( W \) is the work done (energy consumed) and \( t \) is the time taken.
Given energy \( W = 1000 \text{ Joules} \).
Given time \( t = 10 \text{ seconds} \).
Substitute the values into the formula:
\( P = 1000 \text{ J} / 10 \text{ s} \)
\( P = 100 \text{ Watts} \).
Therefore, the average power consumed by the device is 100 Watts.
Name Surname: .................................. Date: .... / .... / 202...
Alternating Current Concepts: Cycle, Period, Frequency, Capacitors, Inductors, Power, and Work Worksheet
SCORE
A. True (T) / False (F)
( .... )
Alternating Current (AC) flows in only one direction.
( .... )
The period of an AC waveform is the time it takes for one complete cycle.
( .... )
A capacitor stores energy in a magnetic field.
( .... )
Frequency is measured in Hertz (Hz).
( .... )
Work is the rate at which energy is transferred or used.
B. Fill in the Blanks
1)
The number of complete cycles of an alternating current that occur in one second is called its .....................
2)
An .................... is an electrical component that stores energy in an electric field.
3)
The unit for electrical power is the .....................
4)
An .................... is an electrical component that resists changes in current flow.
5)
In AC circuits, electrical .................... is done when charge is moved against an electric potential difference.
C. Matching Concepts
( .... )
One complete oscillation or repetition of an AC waveform.
- Period
( .... )
The time required to complete one full cycle of an AC waveform.
- Cycle
( .... )
The number of cycles per second, measured in Hertz.
- Inductor
( .... )
A device that stores electrical energy in an electric field.
- Frequency
( .... )
A device that stores energy in a magnetic field when current flows through it.
- Capacitor
D. Short Answer Questions
1)
Briefly explain the main difference between Alternating Current (AC) and Direct Current (DC).
2)
What is the relationship between period (T) and frequency (f) in an AC circuit?
E. Multiple Choice Questions
1)
Which of the following components stores electrical energy in an electric field?
A) ResistorB) InductorC) CapacitorD) Diode
2)
If an AC waveform completes 60 cycles in one second, what is its frequency?
A) 1 HzB) 60 HzC) 0.0167 HzD) 120 Hz
3)
The rate at which work is done or energy is transferred in an electrical circuit is defined as:
A) WorkB) EnergyC) PowerD) Current
F. Open-Ended Questions
1)
An alternating current has a frequency of 50 Hz. Calculate its period.
2)
Describe the primary function of an inductor in an AC circuit.
3)
If an electrical device consumes 1000 Joules of energy over a period of 10 seconds, calculate the average power consumed by the device.