Question

I have a special thermos that has a vacuum chamber between my hot soup and its outside wall. Because my soup is isolated from its surrounding by a vacuum,

A. My soup will stay warm forever because thermal energy cannot pass through a vacuum.
B. My soup will cool down because of conduction.
C. My soup will cool down because of radiation.
D. My soup will cool down because of convection.E. Both B and D.

Answer 1

C. My soup will cool down because of radiation.

Step-by-step explanation:

Since, there is vacuum between hot soup and its outside wall, then heat can not flow through conduction and convection.

The heat then only flows through radiation.

Therefore, the soup will not cool down because of convection or conduction by because of radiation.