Q18.An electron of mass m and magnitude of charge e at rest, gets accelerated by a constant electric field E . The rate of change of de-Broglie wavelength of this electron at a time t is (ignore relativistic effects) (1) dλ dt = − eEth (2) dλdt = −2heEt (3) dλ dt = −2heEt2 (4) dλdt = − eEt2h
What This Question Tests
This problem combines concepts of de-Broglie wavelength with the mechanics of a charged particle accelerating in a uniform electric field, requiring differentiation to find the rate of change of wavelength.
Concepts Tested
Formulas Used
λ = h/p
F = eE
p = mv
v = at
📚 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 ?
12.5 — A Hydrogen Atom Initially In The Ground Level Absorbs A Photon,
Physics Class 12 · Chapter 12
12.5 A hydrogen atom initially in the ground level absorbs a photon, which excites it to the n = 4 level. Determine the wavelength and frequency of photon.
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?
📋 Question Details
- Chapter
- Dual Nature of Matter
- Topic
- de-Broglie Wavelength
- Year
- 2020
- Shift
- 09 Jan Shift 2
- Q Number
- Q18
- Type
- MCQ
- NCERT Ref
- Class 12 Physics Ch 11: Dual Nature of Matter
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