One-dimensional chain with one atom per unit cell: we have determined the phonon dispersion relation for an infinite chain of atoms with lattice spacing a and one atom per unit cell (mass m). the result is (4.10). for longitudinal vibrations, sketch how the atoms would move for k close to 0 (k p/a) and for k at the brillouin zone boundary (k = p/a).

true tan speed = ang vel x radius

molecules are free to separate from each other and will take on the shape of the container. molecules move completely at random and high speeds. they vibrate in a fixed position and do not move around much. molecules expand to the edge of their container.

according to jean piaget, in what stage of cognitive development are children able to understand conservation task?

b. preoperational

just took it