Match the temperature of a black body given in List-I with an appropriate statement in List-II, and choose the correct option. [Given: Wien’s constant as 2.9 × 10−3 m-K and β„Žπ‘ 𝑒 = 1.24 × 10−6 V-m] List-I List-II (P) 2000 K (1) The radiation at peak wavelength can lead to emission of photoelectrons from a metal of work function 4 eV. (Q) 3000 K (2) The radiation at peak wavelength is visible to human eye. (R) 5000 K (3) The radiation at peak emission wavelength will result in the widest central maximum of a single slit diffraction. (S) 10000 K (4) The power emitted per unit area is 1/16 of that emitted by a blackbody at temperature 6000 K. (5) The radiation at peak emission wavelength can be used to image human bones. (A) 𝑃 → 3,𝑄 → 5, 𝑅 → 2, 𝑆 → 3 (B) 𝑃 → 3,𝑄 → 2, 𝑅 → 4, 𝑆 → 1 (C) 𝑃 → 3,𝑄 → 4, 𝑅 → 2, 𝑆 → 1 (D) 𝑃 → 1,𝑄 → 2, 𝑅 → 5, 𝑆 → 3

 To solve this problem, we need to match the temperature of a black body given in List-I with the appropriate statement in List-II using Wien's displacement law and the given constants.

Step 1: Understand Wien's Displacement Law

Wien's displacement law states that the wavelength at which a black body emits the most radiation (peak wavelength, Ξ»max) is inversely proportional to its temperature T:

Ξ»max=bT

where b=2.9×103m-K is Wien's constant.

Step 2: Calculate Ξ»max for Each Temperature

  1. For T=2000K:

    Ξ»max=2.9×1032000=1.45×106m=1450nm

    This is in the infrared region.

  2. For T=3000K:

    Ξ»max=2.9×1033000=9.67×107m=967nm

    This is near the visible region but still mostly infrared.

  3. For T=5000K:

    Ξ»max=2.9×1035000=5.8×107m=580nm

    This is in the visible region (yellow light).

  4. For T=10000K:

    Ξ»max=2.9×10310000=2.9×107m=290nm

    This is in the ultraviolet region.

Step 3: Match Each Temperature with the Correct Statement

  1. P=2000K:

    • The peak wavelength is 1450 nm (infrared). This does not match any of the statements directly, but it is closest to (3) because infrared radiation can result in a wide central maximum in diffraction.

  2. Q=3000K:

    • The peak wavelength is 967 nm (near infrared). This does not match any statement directly, but it is closest to (4) because the power emitted per unit area at 3000 K is less than at 6000 K.

  3. R=5000K:

    • The peak wavelength is 580 nm (visible). This matches (2) because the radiation is visible to the human eye.

  4. S=10000K:

    • The peak wavelength is 290 nm (ultraviolet). This matches (1) because ultraviolet radiation can emit photoelectrons from a metal with a work function of 4 eV.

Step 4: Choose the Correct Option

Based on the above analysis:

  • P3

  • Q4

  • R2

  • S1

The correct option is (C):

C

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