An observer is standing next to the tracks, watching a train approach. The train travels at 30 m/s and blows its whistle at 8,000 Hz as it approaches and then passes by the observer without slowing down. Assuming the speed of sound is 340 m/s, how much of a frequency change did the observer hear?

The frequency heard by the observer will be "7351.35 Hz".

Explanation:

The given values are:

Source,

Frequency of source,

Speed of sound,

As we know,

⇒  

Here,

So that the formula will be:

⇒  

the simple machine has three main features. they are:

fulcrum is the center point or pivot point of the machine. effort is input force/ applied force. load is external force/ output.

the keisha 's machine labels are

x : load

y: fulcrum

z: lever