Question

Which of the following does not radiate heat? a) ice cube b) liquid nitrogen c) liquid helium d) a device at \(T=0.010 \mathrm{~K}\) e) all of the above f) none of the above

Short answer

a) Ice Cube b) Liquid Nitrogen c) Liquid Helium d) Device at T = 0.010 K e) All of the Above f) None of the Above Answer: None of the options meet the criterion of not radiating heat, as they are all at temperatures above absolute zero.

Step-by-step solution

Option a: Ice Cube

Ice cubes are at a temperature of around 273 K (0°C), and since they are above absolute zero, they will emit thermal radiation according to the Stefan-Boltzmann law. Therefore, they do radiate heat.

Option b: Liquid Nitrogen

Liquid nitrogen has a boiling point of 77 K and is a cooling agent. It is also above absolute zero, which means it radiates heat, albeit at a relatively low rate compared to high-temperature objects.

Option c: Liquid Helium

Liquid helium has a boiling point of about 4.2 K. Even though this is extremely close to absolute zero, it is still above it, so it does emit thermal radiation, although at a very low rate.

Option d: Device at T = 0.010 K

The device with a temperature of 0.010 K is extremely close to absolute zero, but not quite there, so it still radiates a small amount of thermal radiation.

Option e: All of the Above

Since options a through d do radiate heat, option e is incorrect.

Option f: None of the Above

Option f would be correct if none of the given options were true. However, since Options a, b, c, and d do radiate heat, this option is also incorrect. To summarize, all of the options given radiate heat to some extent because they are at temperatures above absolute zero. As a result, none of the options meet the criterion of not radiating heat.