NEET
- Exam
- NEET
- Subject
- Physics
- Chapter
- Dual Nature of Matter
NEET · Physics · Dual Nature of Matter
Given below are two statements: One is labelled as Assertion (A)...
Given below are two statements: One is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion (A) : In Davisson-Germer experiment wavelength associated with the beam decreases with increases of speed of electrons.
Reason (R) : Wavelength associated with electron beam in Davission-Germer experiment is given by (\lambda=\frac{\mathrm{h}}{\sqrt{2 \mathrm{mK}}})
In the light of the above statements, choose the most appropriate answer from the options given below:
Options
- ABoth (A) and (R) are true and (R) is the correct explanation of (A).
- BBoth (A) and (R) are true and (R) is NOT the correct explanation of ((\mathrm{A})).
- C(A) is true but (R) is false.
- D(A) is false but (R) is true.
Correct answer
A. Both (A) and (R) are true and (R) is the correct explanation of (A).
Step-by-step solution
To analyze the statements:
Assertion (A): "In Davisson-Germer experiment, the wavelength associated with the beam decreases with an increase in the speed of electrons."
- This statement is true. According to de Broglie's hypothesis, the wavelength (\lambda) is inversely proportional to the momentum of the particle, which is related to its speed. As the speed of electrons increases, the wavelength decreases.
Reason (R): "Wavelength associated with the electron beam in Davisson-Germer experiment is given by (\lambda=\frac{h}{\sqrt{2 m K}})."
- This statement is also true. The formula given represents the de Broglie wavelength for particles, where is Planck's constant, is the mass of the electron, and is the kinetic energy.