Download App

Sound — Science STD 9 — Question

Gujarat BoardEnglish MediumSTD 9ScienceSound1 Mark
MCQ
In $\text{SONAR},$ we use
  • ✓
    Ultrasonic waves.
  • B
    Infrasonic waves.
  • C
    Radio waves.
  • D
    Audible sound waves.
✓

Answer

Correct option: A.
Ultrasonic waves.
$\text{SONAR} ($sound navigation ranging$)$ uses ultrasonic waves i.e. sounds having frequency greater than $20,000Hz.$
The reasons are:
  1. They can penetrate water to long distances $($because of their high frequency and very short wavelength$)$ unlike ordinary sound waves or infrasonic waves.
  2. Sound of these waves do not get mixed with engine noises or other sounds made by the ship. So, no confusion arises as these waves are not audible by human ear.

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Explore more

More "M.C.Q. [1 M]" from Sound→Sound — all question types→Science STD 9 question papers→Gujarat Board STD 9 question papers→Gujarat Board question paper generator→

Similar questions

Find out incorrect sentence:
→
Indirect transmission of disease is _______:
→
You pull your hands back while catching a fast moving cricket ball. Which law is used to explain it:
→
Organisms causing elephantiasis belongs to phylum:
→
Write the approximate weight of a body of mass $5\ kg:$
→
When a body falls freely towards the earth, then its total energy:
→
Simple epithelium is a tissue, which form the outer protective layer of the skin of the animal body, is composed of cells which are:
→
Which of the following is true for relative density?
→

When a car runs on a circular track with a uniform speed, its velocity is said to be changing. This is because:

    →
    1. Falling coconut$:$ Kinetic energy
    2. Stone on tower$: …………………$
    →