Sonar

Q.

How do you relax for an ECG?

Q. What does radar and sonar mean

Q. Why does light bend around the very small corners and not around the usual size ones?

Q.

Which waves are used in sonar to find the depth of a sea state?

Q. The method used in SONAR is:

1. Echo ranging
2. Ultrasonography
3. Echocardiography
4. Electrocardiography

Q.

Sonar uses a sound of frequency less than 20 Hz.

1. True
2. False

Q.

A ship equipped with a sonar produces an ultrasonic sound wave. The wave took 2 s to reach the receiver after being reflected by a sunken ship directly below it. If the velocity of waves in sea water is 1450 m/s, find the depth at which sunken ship is located.

1. 2900 m

2. 1450 m

3. 2800

4. 3000

Q.

What are the applications of sound?

Q. An oil tanker explodes in the sea. At that instant an aircraft and a submarine were present vertically above and below the oil tanker respectively at equal distances from it. Find the ratio of the time taken by sound waves to reach them. (Speed of sound in air = $320m{s}^{-1}$. Speed of sound in sea water = $1520m{s}^{-1}$)

1. 17 : 8
2. 15 : 9
3. 18 : 5
4. 19 : 4

Q.

In SONAR, we use

1. ultrasonic waves

2. infrasonic waves

3. audible sound waves

4. radio waves

Q. How did scientists found the speed of sound in blood?????Did they kill a person, take his blood then then check it???or how

Q. Which type of frequency do bats use for echolocation?

1. Sonic
2. Ultrasonic
3. Infrasonic
4. Supersonic

Q.

An ultrasonic wave is sent from a ship towards the bottom of the sea. It is found that the time interval between the sending and the receiving of the wave is $1.5s$. Calculate the depth of the sea, if the velocity of sound in sea water is $1400{\mathrm{ms}}^{-1}$.