Question

Consider a hot, boiled egg in a spacecraft that is filled with air at atmospheric pressure and temperature at all times. Disregarding any radiation effect, will the egg cool faster or slower when the spacecraft is in space instead of on the ground? (a) faster (b) no difference (c) slower (d) insufficient information

Short answer

Disregard any radiation effect. Answer: The egg will cool slower in space.

Step-by-step solution

Understand the cooling process

The cooling process of the boiled egg depends on the heat transfer between the egg and the surrounding air inside the spacecraft. There are two main ways for heat transfer in this scenario: conduction and convection.

Understand Conduction

Conduction is the transfer of heat through a solid or stationary fluid due to a temperature difference. In this case, we are considering the transfer of heat from the egg to the air inside the spacecraft. The rate of conduction depends on factors such as the conductivity of the materials, the temperature difference between the egg and the air, and the surface area through which the heat is being transferred.

Understand Convection

Convection is the transfer of heat in a fluid, like air, due to the movement of its particles that occurs when it is heated. In this case, we are considering the movement of the air particles inside the spacecraft as they transfer heat from the egg. The rate of convection depends on factors such as the temperature difference between the egg and the air, the speed at which the air particles are moving, and the specific heat capacity of the air.

Compare the factors in space and on the ground

In both scenarios (in space and on the ground), the air pressure and temperature inside the spacecraft remain constant, which means that the primary factors affecting the cooling process (temperature difference, conductivity, and specific heat capacity) do not change. However, the gravitational force affects the convection process in both cases. On the ground, the gravitational force results in convective currents, which aid in the faster transfer of heat from the egg to the surrounding air. In space, there is no gravitational force, and therefore, the convective currents are absent or significantly weaker. This means the rate of convection will be slower in space than on the ground.

Determine the answer

The absence of convective currents in space will result in a slower cooling process for the boiled egg. So compared to being on the ground, the egg will cool slower in space. Therefore, the correct answer is (c) slower.