“12th Class Physics Chapter 16: Alternating Current” introduces the very concept of alternating current (AC) in students, which is a type of current they use in homes, industry, and power distribution systems. This chapter is very important for MDCAT students, as it builds up a very strong foundation regarding the transmission of electrical energy over long distances. Our MDCAT Quizzes on this chapter will surely test your knowledge and prepare you for examination questions based on alternating current.
Overview of Alternating Current
Alternating current (AC) is different from direct current (DC) because it periodically reverses direction. This chapter opens with a description of the most basic characteristics: amplitude, frequency, and phase of AC. The frequency measured in hertz (Hz) refers to the number of times the current changes direction per second. Students are expected to know the peak value of an alternating current—maximum current—and the rms value of the current, which gives the effective value of the current with regard to its heating effect. The relationship between the peak value and the rms value is obtained and the concept of phase difference in AC circuits is introduced.
AC Circuits
The chapter continues with a detailed explanation of AC circuits, which may include resistors, inductors, and capacitors. In a purely resistive AC circuit, the current and voltage are in phase; that is, they reach their maximum values at the same time. However, in circuits containing inductors and capacitors, the current and voltage are out of phase. Inductive reactance and capacitive reactance are introduced, explaining how inductors and capacitors oppose changes in current. Students will learn how to calculate the total impedance in an AC circuit, which is the combined opposition of resistance and reactance. The concept of resonance in an RLC (resistor, inductor, capacitor) circuit is also covered, explaining how resonance occurs when the inductive reactance and capacitive reactance cancel each other out.
Power in AC Circuits
This will become crucial in dealing with power in AC circuits for practical applications in power generation and transmission. In the chapter on average power and instantaneous power in an AC circuit, power fluctuates as current and voltage change directions. The concept of the power factor is treated thoroughly since it is defined as the ratio between real power to apparent power. When the power factor equals 1 or 100%, then all energy supplied to the circuit is fully utilized; otherwise, there is inefficiency involved. Students shall be able to determine the power consumed in an AC circuit and how the power factor enters into the consumption of energy.
Transformers and Power Transmission
This is, in fact, the major use of alternating current, using transformers to change voltage levels for transfer over long distances. In this chapter, you shall learn the details of how it works by the principle of electromagnetic induction. It consists of two coils: one, called the primary, where the voltage comes in, and the other, called the secondary, where the output voltage is obtained. The change of voltage depends upon the turns ratio of the coils. You shall learn about step-up and step-down transformers and how they are applied in the long-distance transmission of power.
MDCAT Quiz: Test Your Knowledge of Alternating Current
The MDCAT Quiz of Chapter 16 pertains to some critical subjects like AC circuits, resonance, power in AC circuits, impedance, and how a transformer works. This will assess your understanding and help you judge how best you have been prepared to take on MDCAT questions about alternating current.
Free Flashcards for Alternating Current
For quick revision, use free flashcards for Chapter 16. These flashcards cover important topics such as AC circuits, power in AC circuits, impedance, transformers, and resonance. Flashcards are a very effective tool for reinforcing key concepts and formulas so that they become easier to recall during your MDCAT preparation.
By mastering “12th Class Physics Chapter 16: Alternating Current,” students will have a deep understanding of how alternating current works, its applications, and why it is important in the generation and transmission of power. Use our MDCAT Quiz and free flashcards to solidify your knowledge and boost your confidence for MDCAT success.
- Test Name: 9th Class Physics Chapter 1 Quiz
- Type: Quiz Test
- Total Questions: 40
- Total Marks: 40
- Time: 40 minutes
Note: Answer of the questions will change randomly each time you start the test, once you are finished, click the View Results button.
Get Your Username and Password for MDCAT Tests
Sign Up Now
Download Certificate of Quiz Quantum Entanglement
On the end of Quiz, you can download the certificate of the quiz if you got more than 80% marks. Add a certificate to your job application or social profile (like LinkedIn) and get more job offers.
Experience the real exam environment with our expertly designed collection of over 25,000 MCQs MDCAT Mock Tests.
