The answer here would be infrared waves. Hot objects and humans give off heat in the form of infrared light, thermal imaging technology in the goggles enable them to catch this light emitted by these objects
High frequency , it is because wavelength is inversely proportional to frequency
Answer:
Chemical, mechanical, thermal i guess
technically usually the warmer object/substances particles move master which causes friction among the particles plus the kinetic energy being converted to thermal energy, so i would say the hand.
