Amplitude Modulation MCQs
Amplitude modulation (AM) is a modulation process in which the amplitude of a high-frequency sine wave (called a radio frequency) is overlapped with the modulating signal m(t). The modulating signal contains the information like audio data, as in AM radio broadcasting, or two-way radio communications. The high-frequency sinusoidal waveform (i.e., carrier) is modulated by combining it with the message signal using a mixer. A carrier signal is modulated only in amplitude value. The modulating signal is the envelope of the carrier. The required bandwidth for amplitude modulation is two times that of signal to be modulated.
Following are some important advantages and disadvantages of Amplitude modulation:-
Advantages
- It is simple to implement
- It can be demodulated using a circuit consisting of very few components
- AM receivers are cheap
Disadvantages
- It is not efficient with respect to power usage
- It is not efficient in bandwidth; requires a bandwidth equal to twice the highest audio frequency
Q.1) The process of high frequency sine waves are overlapped with the modulated signal is known as……
a) Frequency modulation
b) Amplitude Modulation
c) Phase modulation
d) None of this.
Q.2) Which among the following is kept constant while amplitude modulation?
a) Frequency
b) Wavelength
c) Amplitude
d) all of these.
Q.3) The band with required for the amplitude modulation is….
a) two times the modulated signal
b) three times the modulated signal
c) four times the modulated signal
d) same as modulated signal
Q.4) High frequency carrier wave and modulating analogue signal are combined with the help of…
a) transducer
b) receiver
c) transmitter
d) mixer
Q.5) Amplitude modulation is most commonly used in transmission of
a) digital signal
b) analogue signal
c) both ‘a’ and ‘b’
d) none of these
Q.6) Which among the following is correct for amplitude modulation.
a) It is simple to implement
b) It can be demodulated using a circuit consisting of very few components
c) It is economical mode of transfer of signal
d) all of these
Q.7) Which of the following uses the technique of amplitude modulation
a) radio broadcasting
b) television broadcasting
c) both ‘a’ and ‘b’
d) none of these
Q.8) Bandwidth for amplitude modulation is
a) 5 kHz
b) 10 kHz
c) 50 kHz
d) 100 kHz
Q.9) Which of the following is not true for the Amplitude modulation.
a) It is very efficient with respect to power usage.
b) The range of Amplitude modulated signal is less.
c) The demodulation process is inexpensive.
d) none of these
Answers:
Q.1) b) Amplitude Modulation
Q.2) a) Frequency
Q.3) a) two times the modulated signal
Q.4)d) mixer
Q.5) c) both ‘a’ and ‘b’
Q.6) d) all of these
Q.7) c) both ‘a’ and ‘b’
Q.8) b) 10 kHz
Q.9) a) It is very efficient with respect to power usage.
