You clap in hall and hear an echo after 0.5 s. If speed of sound in air is 340 m/s. Class 9

You clap in hall and hear an echo after 0.5 s. If speed of sound in air is 340 m/s. Class 9

Question 1.

You clap in hall and hear an echo after 0.5 s. If speed of sound in air is 340 m/s, calculate the distance from wall. Class 9

Answer:

Sound travel distance from person to wall and back for an echo = speed of sound in air x time.

Thus, distance of person from wall = ½ × speed of sound in air × time = ½ × 340 × 0.5 = 85 m

Question 2.

A naval sonar signal sent into water returns after 0.90 s. Speed of sound in water is 1530 m/s. How far is the object? Class 9

Answer:

Sound travel distance from sonar to object and back to sonar = speed of sound in water × time.

Thus, distance of sonar from object = ½ × speed of sound in water × time = ½ × 1530 × 0.90 = 688.5 m