debye specific heat

[angelronnie]

Dear people,
I looked through the web and found a definition of debye secific heat and here is what it says:
The specific heat of a solid under the assumption that the energy of the lattice arises entirely from acoustic lattice vibration modes which all have the same sound velocity, and that frequencies are cut off at a maximum such that the temperature
of modes equals the numbers of degrees of freedom of the solid.

but i would like to know what the word "modes" and the word "degrees of freedom" means.
can anyone help me with this definition? :oops:

[angelronnie]

can someone please help :cry:

[RobJim]

I'm not sure what 'modes' are, but you can look here:

http://en.wikipedia.org/wiki/Mode

Degrees of freedom (DOF) are the number of dimensions in which something can move. For example, there can be up to three translational DOFs for most objects; x, y and z. There are also rotational DOFs; one about each of the three axes for objects which are not rotationally symmetric about that axis, and vibrational DOF if there are chemical bonds which can stretch and compress like springs...

[angelronnie]

thank you so much