Q52.A source of monochromatic radiation wavelength 400 nm provides 1000 J of energy in 10 seconds. When this radiation falls on the surface of sodium, x × 1020 electrons are ejected per second. Assume that wavelength 400 nm is sufficient for ejection of electron from the surface of sodium metal. The value of x is ______. (Nearest integer) h = 6 . 626 × 10-34 Js
What This Question Tests
This question combines the concept of photon energy with the photoelectric effect, requiring calculation of the number of photons (and thus electrons) ejected per second given total energy and wavelength.
Concepts Tested
Formulas Used
E = hc/λ
Number of photons = Total Energy / Energy per photon
📚 NCERT Sections This Tests
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📋 Question Details
- Chapter
- Dual Nature of Matter
- Topic
- Photoelectric effect and photon energy
- Year
- 2021
- Shift
- 25 Jul Shift 1
- Q Number
- Q52
- Type
- Numerical
- NCERT Ref
- Class 12 Physics Ch 11: Dual Nature of Radiation and Matter