Question

for an astronaut working outside a spaceship the greatest loss of heat would occur by means of which mode of heat transfer

Answer 1

Radiation, for that doesn't need any medium

Answer 2

For an astronaut working outside a spaceship the greatest loss of heat would occur by means of radiation.

Radiation is the transmission of energy in the form of waves or particles through space or through a material medium. Since he is in space, he would lose heat through radiation.

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