Question

Maximum emission of radiation from the sun takes place at the wavelength

• A. 0.45 μm
• B. 0.55 μm
• C. 0.90 μm
• D. 1.0 μm

Hint:

Solar spectrum:
- Peak emission: ~0.5 μm (visible).
- Wien's law: \(\lambda_{max} = 2898/T\).
- Sun's temperature: ~5778 K, \(\lambda_{max}\) ≈ 0.5 μm.

Answer 1

The Correct Option is A

Step 1: Understanding the Concept:
The Sun behaves approximately as a blackbody radiator, and its maximum energy emission occurs in the visible region of the electromagnetic spectrum.

Step 2: Key Formula or Approach:
According to Wien's displacement law: \[ \lambda_{\max}=\frac{2898}{T} \] where \(T\) is the surface temperature of the Sun in Kelvin.

Step 3: Detailed Explanation:
The average surface temperature of the Sun is about \(5800\,\text{K}\).
Substituting this value into Wien's law gives the wavelength of maximum emission close to the visible region.
The peak lies between \(0.45\) and \(0.55\,\mu\text{m}\), which corresponds to blue-green light.
According to the given answer key, the wavelength of maximum solar emission is \(\mathbf{0.45\,\mu m}\).
Final Answer:
Therefore, the correct answer is (A) 0.45 \(\mu\)m.