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ApoorvGoel
Apr 21, 2011, 02:03 PM
Q. Length of a string tied to 2 rigid bodies is 40cm. Max length(wavelength in cm) o a stationary ave produced on it, is
a.)20
b.)80
c.)40
d.)120

Please give your ans with correct explanations

Unknown008
Apr 22, 2011, 09:03 AM
The largest wavelength you can have is when you have two nodes at the two extremities.

The distance between the two nodes is 40 cm.

Can you find the wavelength?

ApoorvGoel
Apr 22, 2011, 03:32 PM
Please tell me the formula to calculate wavelength

Unknown008
Apr 23, 2011, 08:07 AM
There is no formula for that, unfortunately. It's all about thinking!

See this article, more precisely, the first image you see in the article, first line.

Fundamental frequency - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Fundamental_frequency)

Do you see the position of the string when it is made to vibrate and a stationary wave is produced. The first one is where the max length is obtained.

I assume you know the shape of a wave, and from this, you should be able to 'see' how much of the wave is present on the stationary wave and from there, deduce the wavelength.

ApoorvGoel
Apr 26, 2011, 01:45 PM
Thanks a lot for your answer

Unknown008
Apr 27, 2011, 09:31 AM
And... your answer was? :)

ApoorvGoel
Apr 27, 2011, 02:44 PM
80

Unknown008
Apr 28, 2011, 08:17 AM
Good! :)