Understanding higher speed of sound in a solid...

[riseNshine]

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Hi guys, I understand speed is proportional to the square of young's modulus over density and due to the high stiffness in a solid, speed is greater. However, if speed is greater, that means the wavelength is greater. If there is more compression adn atoms are getting closer together, then how is the wavelength greater?

Oh and another question:
For light which is a transverse wave, do both E and B oscillate at right angles to the propagation vector or is it only B? I wrote both in my notes, but don't understand why E would be at a right angle..

Thanks

 

[gwjib04]

However, if speed is greater, that means the wavelength is greater. If there is more compression adn atoms are getting closer together, then how is the wavelength greater?

Oh and another question:
For light which is a transverse wave, do both E and B oscillate at right angles to the propagation vector or is it only B? I wrote both in my notes, but don't understand why E would be at a right angle..

The speed of a wave in a given material is a fixed value. For example, sound waves travel in air at 340 m/s. As you have pointed out, this is a Bulk phenomenon so the restoring force is greater in a denser medium such as water. Therefore, they will travel faster in water. The wavelength of the wave in 2 different mediums will vary because its speed is different but in both cases it will be proportional to the wavelength and frequency of the wave.

Both E and B are at right angles to each other and to the direction of propagation.
This is where you will use the Right Hand Rule!