A rock under water is 1595 m deep. Find the time in which an ultrasonic signal returns after reflection from the rock. Speed of ultrasonic waves in water = `1450m//s`.

A rock under water is 2900 m deep. Calculate the time in which an ultrasonic signal will return after reflection from the rock. Take velocity of ultrasonic waves in water = 1.45 km//s.

(a) What is sonar? Explain its use. (b) A sonar station picks up a return signal after 3 seconds. How far away is the object? (Speed of sound in water = 1440 m//s) .

A ship produces ultrasonic sound which is collected in 8 s after reflection from the surface of sea. If the velocity of ultrasonics is 1531ms^-1 , then what is the distance of sea surface from sea ?

Write the following statements in a sequential order to find the depth of the ocean bed by the using sonar . (A) The depth of the ocean bed can be found by d = (vt)/(2) . (B) At the bottom of a ship two devices , one is transmitter which products ultrasonics and a receiver for the detection of the reflected ultrasonics from the ocean bed are fixed . (C) The velocity fo ultrasonics in ocean water is 'v' and the time taken to receive the reflected ultrasonics from the ocean bed be 'f'. (D) If the depth of ocean bed is 'd' , then v = (d + d)/(t) = (2d)/(t) .

A message was transmitted from boat which returned to the sender after reflection from the bottom of the sea in 0.8 s. If the velocity of sound in water is 1500ms^-1 then find the depth of sea.

A SONAR system fixed in a submarine operates at a frequency 50 kHz. It is moving towards a rocky hill present inside water with a speed of 432 km h^(-1) . What is the apparent frequency of sound observed at the submarine after reflection by the rocky hill ? (Take velocity of sound in water to be 1450 m s^(-1) )

Two submarines are approaching each other in a calm sea. The first submarine travels at a speed of 36 km h^-1 and the other at 54 km h^-1 relative to the water. The first submarine sends a sound signal (sound waves in water are also called sonar) at a frequency of 2000 Hz. (a) At what frequency is this signal received by the second submarine ? (b) The signal is reflected from the second submarine. At what frequency is this signal received by the first submarine. Take the speed of the sound wave in water to be 1500 m s^-1 .