A sound absorber attenuates the sound level by 20 dB. The intens

Previous Year Papers

Download Solved Question Papers Free for Offline Practice and view Solutions Online.

Test Series

Take Zigya Full and Sectional Test Series. Time it out for real assessment and get your results instantly.

Test Yourself

Practice and master your preparation for a specific topic or chapter. Check you scores at the end of the test.
Advertisement

 Multiple Choice QuestionsMultiple Choice Questions

1.

Arrange the following electromagnetic radiations per quantum in the order of increasing energy:

A: Blue light
B: Yellow light
C: X-ray
D: Radiowave

  • D, B, A, C

  • A, B, D, C

  • C, A, B, D

  • C, A, B, D

294 Views

2.

Choose the correct statement:

  • In amplitude modulation, the amplitude of the high-frequency carrier wave is made to vary in proportion to the amplitude of the audio signal.

  • In amplitude modulation, the frequency of the high-frequency carrier wave is made to vary in proportion to the amplitude of the audio signal.

  • In frequency modulation, the amplitude of the high-frequency carrier wave is made to vary in proportion to the amplitude of the audio signal.

  • In frequency modulation, the amplitude of the high-frequency carrier wave is made to vary in proportion to the amplitude of the audio signal.

214 Views

3.

A signal of 5 kHz frequency is amplitude modulated on a carrier wave of frequency 2 MHz. The frequencies of the resultant signal is/are:

  • 2005 kHz, and 1995 kHz

  • 2005 kHz, 2000 kHz and 1995 kHz

  • 2000 kHz and 1995 kHz

  • 2000 kHz and 1995 kHz

397 Views

4.

A train is moving on a straight track with speed 20 ms-1 .It is blowing its whistle at the frequency of 1000 Hz. The percentage change in the frequency heard by a person standing near the track as the train passes him is (speed of sound = 320 ms-1 ) close to :

  • 6%

  • 12%

  • 18%

  • 18%

472 Views

Advertisement
5.

A diode detector is used to detect an amplitude modulated wave of 60% modulation by using a condenser of capacity 250 pico farad in parallel with a load resistance 100 kilo ohm. Find the maximum modulated frequency which could be detected by it. 

  • 10.62 MHz

  • 10.62 kHz

  • 5.31 mHz

  • 5.31 mHz

313 Views

6.

A radar has a power of 1 Kw and is operating at a frequency of 10 GHz. It is located on a mountain top of height 500 m. The maximum distance upto which it can detect object located on the surface of the earth (Radius of earth = 6.4 x 106 m) is

  • 80 km

  • 16 km

  • 40km

  • 40km

321 Views

7.

This question has Statement 1 and Statement 2. Of the four choices given after the statements, choose the one that best describes the two statements. 
Statement 1 - Sky wave signals are used for long distance radio communication. These signals are in general, less stable than ground wave signals.
Statement 2- The state of ionosphere varies from hour to hour, day to day and season to season.

  •  Statement 1 is true, statement 2 is false. 

  • Statement 1 is true, Statement 2 is true, Statement 2 is the correct explanation of Statement 1

  •  Statement 1 is true, Statement 2 is true, Statement 2 is not the correct explanation of Statement 1

  •  Statement 1 is true, Statement 2 is true, Statement 2 is not the correct explanation of Statement 1

233 Views

Advertisement

8.

A sound absorber attenuates the sound level by 20 dB. The intensity decreases by a factor of

  • 1000

  • 10000

  • 10

  • 10


D.

10

491 Views

Advertisement
Advertisement
9.

In a full wave rectifier circuit operating from 50 Hz mains frequency, the fundamental frequency in the ripple would be

  • 50 Hz

  • 25 Hz

  • 100 Hz

  • 100 Hz

285 Views

10.

A telephonic communication service is working at carrier frequency of 10 GHz. Only 10% of it is utilized for transmission. How many telephonic channels can be transmitted simultaneously if each channel requires a bandwidth of 5 kHz?

  • 2 x 106

  • 2 x 105

  • 2 x 104

  • 2 x 105


Advertisement