The rope wave generator in the photograph below consists of a rope attached at one end to a vibrator with the other end running over a pulley with 1000 grams of weight attached. When the vibrator is activated, a one loop standing wave is produced, as shown in an mpeg video by clicking your mouse on the photograph.
If the video goes too fast for you, click here to see it at a reduced speed. Note that the string vibrates four times (the sound of the rope wave generator) for each tick of the metronome.
For this video, the metronome is set to 160 ticks per minute, and there are four vibrations of the wave generator per metronome tick, so the frequency of the wave generator is 640 vibrations per minute.
Suppose that the tension in the rope is decreased by a factor of 2 by replacing the 1000 gram weight with a 500 gram weight. How must you change the frequency so that a single loop standing wave will result?
To obtain the new frequency the old frequency must be:
Click here for Answer #265 after December 4, 2006.
