Question

two trucks that travel just as quickly come face to face. A driver hears the Horn of the other truck to a frequency that is 1.40 times the queesucha when both trucks are detained. Determine the speed of each truck. (ENGLISH VERSION)

Dos camiones que viajan con la misma rapidez se acercan frente a frente. Un conductor escucha la bocina del otro camión a una frecuencia que es 1.40 veces la que escucha cuando ambos camiones están detenidos. Determine la rapidez de cada camión. (SPANISH VERSION)

Answer 1

The expression for apperent frequency from doppler shift is. 31 - 12 vtv Here, vis velocity of sound in air at room temperature (343m/s) Vo is velocity of observer and v, is the velocity of the source and n is the natural frequency of source Here, vo-v, - v,(velocity of the truck) From the given data, This means both the trucks are approaches each other.The expression is, 2 343mis+ 343m/s-v, 1.4» - 12 solve for velocity of each truck (v)-57 m/s