1) Which properties should be considered most strongly to optimize heat transfer between two solids? Is it their thermal conductivity...or other factors?

2) You can learn a lot about materials by shining a range of different light wavelengths through them and measuring the intensity of light that comes through. If I shine light from 300-1600 nm into a material and note that absorption peaks at 1450 nm and then drops at longer wavelengths:

1. Calculate the band gap (assuming absorption of light is due to electronic transitions from valence band to conduction band)
2. Determine whether or not the material would be transparent or opaque to white light
3. Do you think it is a metallic or nonmetallic material? Why?

3) A magnetic field of strength 10³ A m^-1 is applied to an ideal magnetic material with a linear relationship between B and H. If the relative permeability is 50, calculate the magnetization and susceptibility.