iGCSE Physics (0625) 6.2.1 The Sun as a star-Exam Style Questions- New Syllabus
▶️ Answer/Explanation
Detailed solution:
The Sun is a medium-sized star that emits a broad spectrum of electromagnetic radiation.
According to the syllabus, the Sun radiates the vast majority of its energy in three specific regions: ultraviolet, visible light, and infrared.
The provided pie chart identifies region $P$ as visible light and region $Q$ as ultraviolet radiation.
By process of elimination based on the known primary emissions of the Sun, the remaining large section, region $R$, must represent infrared radiation.
Infrared radiation accounts for a significant portion of the solar energy reaching Earth, primarily felt as heat.
Therefore, Option A is the correct identification for the missing region of the solar emission profile.
▶️ Answer/Explanation
Detailed solution:
The Sun emits a broad spectrum of electromagnetic radiation, but the majority of the energy reaching Earth’s surface is concentrated in specific bands.
According to the syllabus, the Sun radiates most of its energy in the infrared, visible light, and ultraviolet regions of the spectrum.
High-energy radiation like $X-rays$ and $gamma$ rays are emitted in much smaller quantities and are largely filtered by the atmosphere.
Conversely, longer wavelengths like $microwaves$ contribute a negligible fraction of the total solar irradiance received.
Therefore, the combination of ultraviolet, visible, and infrared represents the primary regions of received solar radiation.
This matches the information provided in Option C.
▶️ Answer/Explanation
Detailed solution:
The Sun is a medium-sized star that emits a broad spectrum of electromagnetic radiation.
According to the syllabus, the Sun radiates the vast majority of its energy within three specific regions: infrared, visible light, and ultraviolet.
Visible light accounts for the peak of the Sun’s emission, while significant energy is also radiated as heat (infrared) and higher-energy photons (ultraviolet).
In contrast, regions like microwaves and radio waves represent a negligible fraction of the Sun’s total energy output.
Since options A, C, and D are the primary regions of solar emission, the Sun radiates the least amount of energy in the microwave region.
Therefore, microwave is the correct answer among the given choices.