Wirte Different Methods of Transmission of heat?

Calculate the mass of an object that has a momentum of 100kg x m/sec and velocity of 4 m/sec

Consider an insulating crystal, made up of layers of atoms. what form would you expect the temperature dependence of the phonon heat capacity to approach at extremely low temperatures if the interlayer coupling is i)very strong (rigid coupling), and ii) very weak. explain.

Energy flows from the producer level to the level. is called