When a sound is reflected from a distant object, an echo is produced. Let the distance between the reflecting surface and the source of sound production remains the same. Do you hear echo sound on a hotter day ?

An echo returned in 3 s. What is the distance of reflecting surface from the source ? Given that the speed of sound is 342 ms^ -1 .

An echo is heard after 4s. What is the distance of reflecting surface from the source, given that the speed of sound is 342 ms^-1 .

What is the minimum distance of the obstacle from the source of sound for hearing distinct echo ?

The time between a clap and its echo from a wall is 0.1 s. If the distance of the wall be 17.5 m, calculate the speed of sound.

A SONAR (sound navigation and ranging) uses ultrasonic waves to detect and locate objects under water. In a submarine equipped with a SONAR the time delay between generation of a probe wave and the reception of its echo after reflection from an enemy submarine is found to be 77.0 s. What is the distance of the enemy submarine? (Speed of sound in water = 1450 m s^-1 ).