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NEET UG 2017 · Physics · Question 18

NEET 2017 Physics, question 18

Question 18 of the NEET 2017 paper (code A) is a Physics question from Dual Nature of Radiation and Matter. CBSE dropped it from the official answer key.

Updated 2026-10-08

Q18 · Physics

The photoelectric threshold Wave length of silver is 3250×10−103250\times10^{-10} m. The velocity of the electron ejected from a silver surface by ultraviolet light of wavelength 2536×10−102536\times10^{-10} m is :

(Given h=4.14×10−15h = 4.14\times10^{-15} eVs and c=3×108c = 3\times10^{8} ms−1\mathrm{ms^{-1}})

  1. 1≈6×105\approx 6\times10^{5} ms−1\mathrm{ms^{-1}}
  2. 2≈0.6×106\approx 0.6\times10^{6} ms−1\mathrm{ms^{-1}}
  3. 3≈61×103\approx 61\times10^{3} ms−1\mathrm{ms^{-1}}
  4. 4≈0.3×106\approx 0.3\times10^{6} ms−1\mathrm{ms^{-1}}

No official answer: dropped by CBSE.

The chapter

Dual Nature of Radiation and Matter in ten years of NEET

20 questions from 2017–2026, asked in 10 of 10 papers, about 1.9 a paper. Photoelectric Effect alone had 20.

Chapter analysisStudy this chapterPractise this chapter

Dual Nature of Radiation and Matter: questions per paper

0241’172’181’193’202’212’222’232’242’253’26