AC Source
The AC source is a device that provides alternating current. It generates electrical energy that periodically reverses direction, allowing for the flow of electrons back and forth. Common examples of AC sources include power plants and generators.
AC Graph
The graph of alternating current shows the variation of current over time. The waveform is typically sinusoidal, indicating that the current changes direction periodically. The x-axis represents time, while the y-axis represents current magnitude.
Alternating Current and Voltage
Alternating current (AC) is characterized by its periodic change in direction and magnitude. The mathematical representation of an AC waveform can be expressed as:
I(t) = Imax sin(ωt + φ)
Where:
- I(t): Instantaneous current at time t
- Imax: Maximum current (peak value)
- ω: Angular frequency (ω = 2πf, where f is frequency)
- φ: Phase angle (indicates the phase shift)
Similarly, the alternating voltage can be represented as:
V(t) = Vmax sin(ωt + φ)
Where:
- V(t): Instantaneous voltage at time t
- Vmax: Maximum voltage (peak value)
فہم (Understanding in Urdu)
متبادل کرنٹ (AC) وہ برقی کرنٹ ہے جو وقت کے ساتھ اپنی سمت اور مقدار میں تبدیلی کرتا ہے۔ اس کی خصوصیت یہ ہے کہ یہ مثبت اور منفی دونوں سمتوں میں بہتا ہے۔...
10 Most Repeated MCQs for Punjab Board
- AC is a type of current that:
- A) Flows in one direction
- B) Reverses direction periodically
-
What is the waveform shape of AC?
- A) Square
- B) Sinusoidal
- C) Triangular
- D) Constant
-
The peak value of current is represented by:
- A) I(t)
- B) Imax
- C) V(t)
- D) Vmax
-
What is the primary source of AC?
- A) Battery
- B) Power plants
- C) Solar panels
- D) Capacitors
-
In AC circuits, the voltage can be:
- A) Always positive
- B) Always negative
- C) Both positive and negative
- D) None of the above
-
What does the phase angle in AC indicate?
- A) The frequency of the current
- B) The direction of current flow
- C) The phase difference between voltage and current
- D) None of the above
-
Which device converts AC to DC?
- A) Inverter
- B) Rectifier
- C) Transformer
- D) Capacitor
-
What is the unit of frequency?
- A) Hertz (Hz)
- B) Volts (V)
- C) Amperes (A)
- D) Ohms (Ω)
-
In a sinusoidal AC wave, what is the time period?
- A) The time taken for one complete cycle
- B) The maximum voltage
- C) The average voltage
- D) None of the above
-
Which of the following is true about AC voltage?
- A) It remains constant
- B) It varies sinusoidally with time
- C) It cannot be transformed
- D) None of the above