REFLECTED SOUND ( ECHO )

 

1.    Sonar is emitted from the ship to measure the depth of the sea. It is received by the receiver in 0.8 seconds. If the speed of sound in water is 1500 m/s, calculate the depth of the sea. 

Solution

Data : t = 0.8 s

          V = 1500 m/s

Question : d = ….?

Answer :

d = ( vt ) /2 = ( 1500 m/s x 0.8 s ) : 2 = 600 m

 

2.    Sonar is emitted from the ship to measure the depth of the sea. It is received by the receiver in 1.2 seconds. If the speed of sound in water is 1480 m/s, calculate the depth of the sea.

Solution

Data : t = 1.2  s

          V = 1480 m/s

Question : d = ….?

Answer :

d = ( vt ) /2 = ( 1480 m/s x 1.2 s ) : 2 = 888 m

 

3.    Sonar is emitted from ship. The depth of the sea is 660m. Calculate the time transmitted until it received a back receiver. (The speed of sound in water is 1400 m/s)

Solution

Data : d = 660 m

          V = 1400 m/s

Question : t = ….?

Answer :

t = 2d/v = 2x 660 m : 1400 m/s = 0.94 s

 

4.    Sonar is emitted from ship. The depth of the sea is 1.5 km. Calculate the time transmitted until it is received back by the receiver. (The speed of sound in water is 1500 m/s)

Solution

Data : d = 1.5 km = 1500 m

          V = 1500 m/s

Question : t = ….?

Answer :

t = 2d/v = 2 x 1500 m : 1500 m/s = 2 s

 

5.    Sonar is emitted from the ship. The depth of the sea is 315 m. If the total time after emitting and received back by the receiver is 0.42 s, calculate the speed of sound in water.

Solution

Data : d = 315 m

          t =  0.42 s

Question : v= ….?

Answer :

V = 2d / t = 2x 315 m : 0.42 s = 1500 m/s

 

6.    Sonar is emitted from the ship. The depth of the sea is 1.8 km. If the total time after emitting until it is received back by the receiver is 18/7 seconds. Calculate the speed of sound in the seawater.

Solution

Data : d = 1.8 km = 1800 m

          t = 18/7 s

Question : v = ….?

Answer :

v = 2d/t = 2x 1800 m : 18/7 s = 1400 m/s

7.    Pedro shouts loudly. The sound is reflected back by the wall.  He can hear his echo in 0.22 s. Calculate the distance between Pedro and the wall. The speed of sound in air is 340 m/s.

Solution

Data : v= 340 m/s

          t = 0.22 s

Question : d = ….?

Answer :

d= vt / 2 = 340 m/s x 0.22 s : 2 = 37.4 m

 

8.    Pauline shouts loudly. The sound is reflected back by the wall.  He can hear his echo in 0.40 s. Calculate the distance between Pauline and the wall. The speed of sound in air is 330 m/s.

Solution

Data : v= 330 m/s

          t = 0.40 s

Question : d = ….?

Answer :

d= vt / 2 = 330 m/s x 0.40 s : 2 = 66 m