Wave practice


Wave questions for practice



1.  Draw a wave and identify the primary parts (wavelength, crest, trough, amplitude).



2.  Calculate the speed of a 500 Hz wave with a wavelength of 0.25 m.  Show the full calculation with the formula.



3. What is the frequency of a wave that travels at 24 m/s, if 3 full waves fit in a 12-m space?  (Hint:  find the wavelength first.)



4.  What is the difference between mechanical and electromagnetic waves?  Give examples.



5.  Consider the musical note G, 392 Hz.  Find the following:



a)    The frequencies of the next two G's, one and two octaves above.



b)    The frequency of the G one octave below than 392 Hz.



c)    The frequency of G#, one semi-tone (piano key or guitar fret) above this G.



d)    The frequency of A#, 3 semi-tones above G.



e)    The wavelength of the 392 Hz sound wave, assuming that the speed of sound is 340 m/s.

 

6.  Show how to compute the wavelength of WTMD's signal (89.7 MHz).  Note that MHz means 'million Hz."  Recall that radio waves travel at the speed of light.


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