NEET 2017 · PhysicsMatter wavePrevious Year Question
The de Broglie wavelength of a neutron in thermal equilibrium with heavy water at a temperature T (kelvin) and mass m is:
Answer: (B) h/√(3mkT). Answer: (b) h/√(3mkT) Solution: Thermal kinetic energy: KE = (3/2)kT.
- A.h/√(mkT)
- B.h/√(3mkT)✓
- C.2h/√(3mkT)
- D.2h/√(mkT)
Correct Answer
(B) h/√(3mkT)
Solution & Explanation
Answer: (b) h/√(3mkT) Solution: Thermal kinetic energy: KE = (3/2)kT. Momentum p = √(2m·KE) = √(3mkT). λ = h/p = h/√(3mkT).
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