A FEW QUICK QUESTIONS ABOUT PHYSICs...........?????

[bebe]

1.) If two waves have a frequency of 500 Hz and 504 Hz, what will a.) the beat frequency be between these two waves and b.) what will the frequency of the combined wave equal?

2.) Two sound waves both of frequency 2 kHz interfere at a point. If their path length difference is PLD = 3.3 inches, what type of interference do they undergo? Use v = 1100 ft/s for the waves' speed. (The answer is either constructive or destructive interference.)

Also, what type of interference (destructive or constructive) will the waves undergo if the frequency is 4 kHz?

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