Q26.Electron beam used in an electron microscope, when accelerated by a voltage of 20 kV has a de-Broglie wavelength of λ0 . If the voltage is increased to 40 kV then the de-Broglie wavelength associated with the electron beam would be: (1) 3λ0 (2) 9λ0 (3) λ0 (4) λ0 2 √2
What This Question Tests
This question requires relating the de Broglie wavelength of an electron to the accelerating voltage and calculating the new wavelength upon voltage change.
Concepts Tested
Formulas Used
λ = h/p
p = √(2mE)
E = eV
λ = h/√(2meV)
📚 NCERT Sections This Tests
11.10 — What Is The De Broglie Wavelength Of
Physics Class 12 · Chapter 11
11.10 What is the de Broglie wavelength of (a) a bullet of mass 0.040 kg travelling at the speed of 1.0 km/s, (b) a ball of mass 0.060 kg moving at a speed of 1.0 m/s, and (c) a dust particle of mass 1.0 × 10–9 kg drifting with a speed of 2.2 m/s ?
12.8 — A 12.5 Ev Electron Beam Is Used To Bombard Gaseous Hydrogen At
Physics Class 12 · Chapter 12
12.8 A 12.5 eV electron beam is used to bombard gaseous hydrogen at room temperature. What series of wavelengths will be emitted?
11.3 — The Photoelectric Cut-Off Voltage In A Certain Experiment Is 1.5 V.
Physics Class 12 · Chapter 11
11.3 The photoelectric cut-off voltage in a certain experiment is 1.5 V. What is the maximum kinetic energy of photoelectrons emitted?
📋 Question Details
- Chapter
- Dual Nature of Matter
- Topic
- De Broglie wavelength of electron
- Year
- 2023
- Shift
- 25 Jan Shift 1
- Q Number
- Q26
- Type
- MCQ
- NCERT Ref
- Class 12 Physics Ch 11: Dual Nature of Matter
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