Question 3

The Sun transfers heat to Earth by radiation.

The process through which the Sun transfers heat to Earth is primarily radiation. This form of energy transfer does not require a medium and allows solar energy to travel through the vacuum of space.

A) conduction

Conduction is the transfer of heat through direct contact between materials. Since the Sun's heat reaches the Earth through the vacuum of space and not via direct contact, this option is incorrect.

B) radiation

Radiation is the correct answer as it refers to the transfer of energy in the form of electromagnetic waves, including visible light and infrared radiation. This is how the Sun emits energy, which travels through the vacuum of space and warms the Earth.

C) ionization

Ionization is the process of adding or removing electrons from atoms, which is not related to the transfer of heat. This option does not apply to how the Sun's heat reaches the Earth, making it incorrect.

D) sublimation

Sublimation refers to the transition of a substance from solid to gas without passing through the liquid phase. This process is unrelated to the transfer of heat from the Sun to Earth and is therefore incorrect.

Conclusion

Radiation is unequivocally the correct choice as it accurately describes the mechanism through which the Sun's energy travels through space to heat the Earth. The other options, including conduction, ionization, and sublimation, fail to represent the actual process, highlighting the unique nature of radiation in this context.