Which substance has the most thermal energy and will have the most heat flow from it? a stovetop burner on medium (200°c) a nuclear reactor core (1000°c) the human body (36°c) air at room temperature (32°c)

Internal thermal energy will depends upon its temperature

so here the temperature range will be maximum 1000 degree C

so here maximum thermal energy is given by

A Nuclear Reactor Core

So here the maximum thermal energy and have the most heat flow is given by nuclear reactor core as it has maximum temperature

no. dot product   =0 when vecs at right angles