Wien's law is concerned with: (a) wavelength corresponding to maximum energy and absolute temperature. (b) radiated energy and wavelength. (c) emissive power and temperature. (d) colour of light and temperature.

Options

A. wavelength corresponding to maximum energy and absolute temperature
B. radiated energy and wavelength
C. emissive power and temperature
D. colour of light and temperature

Answer

To solve the question regarding Wien's law, let's go through the steps systematically.

### Step 1: Understand Wien's Law
Wien's law, specifically known as Wien's displacement law, relates the temperature of a black body to the wavelength at which it emits radiation most intensely.

### Step 2: Write the Definition
Wien's displacement law states that the wavelength (λ) corresponding to the maximum intensity of radiation emitted by a black body is inversely proportional to its absolute temperature (T). This can be mathematically expressed as:
\[ \lambda_m \cdot T = b \]
where \( \lambda_m \) is the wavelength at maximum intensity, \( T \) is the absolute temperature, and \( b \) is a constant.

### Step 3: Analyze the Options
Now, let's analyze the given options in the question:

(a) Wavelength corresponding to maximum energy and absolute temperature.
(b) Radiated energy and wavelength.
(c) Emissive power and temperature.
(d) Colour of light and temperature.

### Step 4: Evaluate Each Option
- **Option (a)**: This option is correct because it directly relates to the wavelength at which maximum energy is emitted and its relation to absolute temperature, which is what Wien's law describes.
- **Option (b)**: This option is incorrect as it does not specifically mention the relationship with temperature.
- **Option (c)**: This option is also incorrect because emissive power is not the main focus of Wien's law.
- **Option (d)**: This option is incorrect as it relates color to temperature, which is not the primary concern of Wien's law.

### Step 5: Conclusion
The correct answer is **(a) wavelength corresponding to maximum energy and absolute temperature**.