English

Science (English Medium) Class 12 - CBSE Important Questions

Advertisements
Subjects
Topics
Subjects
Popular subjects
Topics

Please select a subject first

Advertisements
Advertisements
< prev  1761 to 1780 of 5300  next > 

During the formation of a p-n junction ______.

Appears in 2 question papers
Chapter: [14] Semiconductor Electronics - Materials, Devices and Simple Circuits
Concept: Diode or p-n Junction

Explain the terms Attenuation used in Communication System.

Appears in 2 question papers
Chapter: [15] Communication Systems
Concept: Basic Terminology Used in Electronic Communication Systems

Explain any two factors that justify the need of modulating a low-frequency signal.

Appears in 2 question papers
Chapter: [15] Communication Systems
Concept: Amplitude Modulation (AM)

How is amplitude modulation achieved?

Appears in 2 question papers
Chapter: [15] Communication Systems
Concept: Amplitude Modulation (AM)

The frequencies of two side bands in an AM wave are 640 kHz and 660 kHz respectively. Find the frequencies of carrier and modulating signal. What is the bandwidth required for amplitude modulation?

Appears in 2 question papers
Chapter: [15] Communication Systems
Concept: Amplitude Modulation (AM)

Write two advantages of frequency modulation over amplitude modulation.

Appears in 2 question papers
Chapter: [15] Communication Systems
Concept: Amplitude Modulation (AM)

Define the term modulation. Draw a block diagram of a simple modulator for obtaining AM signal ?

Appears in 2 question papers
Chapter: [15] Communication Systems
Concept: Modulation and Its Necessity

Write three important factors which justify the need of modulating a message signal. Show diagrammatically how an amplitude modulated wave is obtained when a modulating signal is superimposed on a carrier wave.

Appears in 2 question papers
Chapter: [15] Communication Systems
Concept: Amplitude Modulation (AM)

In the given block diagram of a receiver, identify the boxes labeled as X and Y and write their functions.

Appears in 2 question papers
Chapter: [15] Communication Systems
Concept: Modulation and Its Necessity

Given modulation index physical significance .For an amplitude modulated wave, the maximum amplitude is found to be 10 V while the minimum amplitude is 2 V. Determine the modulation index μ ?

Appears in 2 question papers
Chapter: [15] Communication Systems
Concept: Modulation and Its Necessity

What do you mean by bandwidth of a signal? Give its importance. 

Appears in 2 question papers
Chapter: [15] Communication Systems
Concept: Bandwidth of Signals

Differentiate between Analog and Digital communication. 

Appears in 2 question papers
Chapter: [15] Communication Systems
Concept: Bandwidth of Signals

Answer the following question.
Why a signal transmitted from a TV tower cannot be received beyond a certain distance? Write the expression for the optimum separation between the receiving and the transmitting antenna.

Appears in 2 question papers
Chapter: [15] Communication Systems
Concept: Modulation and Its Necessity

Answer the following question.
If A and B represent the maximum and minimum amplitudes of an amplitude-modulated wave, write the expression for the modulation index in terms of A and B.

Appears in 2 question papers
Chapter: [15] Communication Systems
Concept: Amplitude Modulation (AM)

Solve the following question.
A message signal of frequency 20 kHz and peak voltage 10 V is used to modulate a carrier of frequency 2 MHz and peak voltage of 15 V. Calculate the modulation index. Why the modulation index is generally kept less than one? 

Appears in 2 question papers
Chapter: [15] Communication Systems
Concept: Amplitude Modulation (AM)

Describe any four consequences of the disintegration of Soviet Union

Appears in 2 question papers
Chapter: [1.1] Cold War Era
Concept: Disintegration of the Soviet Union and Its Impact Or Consequences on the World Order

American involvement in South Asia has rapidly increased after the Cold War. Give two examples to illustrate.

Appears in 2 question papers
Chapter: [1.1] Cold War Era
Concept: India and the Cold War

Identify the group of countries that had been part of the Soviet Union before its disintegration.

Appears in 2 question papers
Chapter: [1.1] Cold War Era
Concept: Disintegration of the Soviet Union and Its Impact Or Consequences on the World Order

What is the full form of “SAARC”?

Appears in 2 question papers
Chapter: [1.2] The End of Bipolarity
Concept: What Was the Soviet System?

Why did the superpowers need smaller states as their allies? Explain any four reasons.

Appears in 2 question papers
Chapter: [1.2] The End of Bipolarity
Concept: Introduction of Democratic Politics and Capitalism in Post-communist Regimes
< prev  1761 to 1780 of 5300  next > 
Advertisements
Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×