A man walks parallel to a railway track with a speed of 1.5 m/s, and a train moves towards him at a speed of 20 m/s. The man hears the train whistle with a frequency of 683 Hz. The speed of sound in air is equal to 340 m/s. What is the frequency of the whistle emitted by the train?

A sprocket has 48 teeth and rotates 330 times per minute. Calculate the frequency of the sound produced by the vibration of a blade touching it.

A person emits a sound in front of a wall and after ¾ of a second hears the echo. Calculate the distance to the wall. The air temperature is 15 °C, and at this temperature, the speed of sound is 340 m/s.

The audible sounds by the human ear result from vibratory movements whose frequencies are between 16 Hz and 20000 Hz. Knowing that at 20 °C, the speed of propagation of sound in water is 1450 m/s and in air 344 m/s. Calculate:
a) The wavelengths corresponding to the maximum and minimum frequencies in air and water;
b) The ratio between the wavelengths in water and air.

A projectile is fired at an angle of 60° to the horizontal and explodes when it hits the ground. Determine the initial velocity of the projectile and the range of the shot, knowing that the starting and ending points are in the same horizontal plane and that the air temperature is 25 °C, assume the speed of sound in air at 0 °C is equal to at 332 m/s.