i'll give brainliest
why the total energy of electron is negative

Electrons are always marked negative Hence electronic energy is also always taken as negative. It is because when an electron is at infinite distance from nucleus , there the kinetic energy of that electron can not be calculated. So, it is taken to be zero . ... And thus the energy of electron becomes less negative

the transfer of heat by electromagnetic radiation is called thermal radiation . it is usually carried out by electromagnetic waves in an energy range just below the visible spectrum, which is the infrared range.

so the answer would be radiation.

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