Physics HELP! Watch
1) A loudspeaker points directly at a wall 3m away and emits a note of frequency 680Hz. A standing wave is formed. If the speed of sound is 340m/s, what will be the separation between minimum intensities (nodes)?
2) A steady note of frequency 850Hz from a works siren is heard by two people standing in an open field. One is 4.0m nearer to the siren than the other. If the speed of sound in air is 340m/s, what is the path difference in metres between the waves reaching the two workers? How many wavelengths is this?
3) Organ pipes can produce very low notes. About how long would a stopped organ pipe closed at one end have to be to produce a note of 30Hz? (Speed of sound 340m/s)