Stationary Waves on Cello String

Basically, one of the strings of a cello has a vibrating length of 0.8m. The string is made to oscillate as a stationary wave by means of a bow and the following pattern of oscillations is seen:

just imagine sinusodal graph; distance against displacement; wavelength is 0.4m

The question (worth 3 marks) asks:

Explain how the movement of the bow causes this wave pattern.

Any ideas?

THanks all!

Anyone ... ? :frown:

If I had to hazard a guess, I'd say it provides a driving frequency = natural frequency of the string, in turn making it resonate and produces the stationary wave.

That's most likely all rubbish though so don't take my word as gospel.

Reply 3

Creative

The stick/slip motion of the bow generates a travelling wave on the string, the travelling wave reflects off the end of the string. The reflected wave and the incoming travelling wave (which are travelling in opposite directions ) superpose to form a stationary wave pattern on the string.

Although the above poster could be right btw. lol :biggrin:

Reply 4

Nikki.x

i'm not saying this is right or anything but...

the bow has halved the length of the string and is therefore creating a node where the bow meets the string. then it goes antinode and then node on the end as the string is attached to the cello.

not entirely sure what else to say...

hope this helps a little?

xxx

Reply 5

Annonym2002

when the bow gives a force to the stretched string, a wave is created on the string. Therefore, when the wave reaches the fixed positions the wave gets reflected towards the opposite direction to the incidence wave created by the bow.This reflected wave is 180 degree out of phase to the first wave. This process creates a stationary wave.