Question

Does any of the energy of the sun reach the earth by conduction or convection?

Short answer

Answer: No, energy from the Sun does not reach Earth through conduction or convection. The primary mode through which energy from the Sun reaches Earth is radiation.

Step-by-step solution

Background on heat transfer

Heat can be transferred by three main modes: conduction, convection, and radiation. 1. Conduction: It is the transfer of heat through a solid material by the movement of free electrons and the vibration of atoms and molecules. It requires direct contact between the objects. 2. Convection: It is the transfer of heat through fluids (liquids or gases) by the movement of the fluid itself. The heated fluid rises, and cooler fluid moves to take its place, creating a circulation pattern that transfers heat. 3. Radiation: It is the transfer of heat through electromagnetic waves, and it does not require any medium to transfer heat.

Conduction and its applicability to the problem

Conduction requires direct contact between objects to transfer heat. In the case of the Sun and Earth, there is no physical connection or direct contact between them (they are separated by the vacuum of space). Therefore, conduction cannot be the mode through which energy from the Sun reaches Earth.

Convection and its applicability to the problem

Convection requires the movement of fluids to transfer heat. The space between the Sun and Earth is not filled with a fluid; it is mostly a vacuum with only a few atoms per cubic centimeter. This extremely low-density medium is not sufficient to transfer heat through convection from the Sun to Earth.

Radiation and its applicability to the problem

Radiation transfers heat through electromagnetic waves that can travel through the vacuum of space. The energy from the Sun reaches Earth through radiation in the form of sunlight, which contains electromagnetic waves, primarily in the visible, ultraviolet, and infrared bands.

Conclusion

Based on our understanding of the three different modes of heat transfer, we can conclude that no energy from the Sun reaches the Earth through conduction or convection. The primary mode through which energy from the Sun reaches Earth is radiation.