Intellectual self - assessment on how your reason and solved problem

Does heating a metal wire increase or decrease its electrical resistance? why?

The two most prominent wavelengths in the light emitted by a hydrogen discharge lamp are 656(red) and 486 (blue). light from a hydrogen lamp illuminates a diffraction grating with 500 lines per mm, and the light is observed on a screen 1.50 behind the grating. what is the distance between the first-order red and blue fringes?

2) the sun is wonderful source of energy. it is renewable and natural with few dangers. solar cells rely on the sun for energy. these cells would be more practical to use if they were