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De-Broglie Waves

 De-Broglie Waves

Particle vs Wave
Particle vs Wave
Difference between particle and wave.

History

The concept that matter behaves like a wave was proposed by De-Broglie. De-Broglie, in his 1924 PhD thesis, proposed that just as light has both wave-like and particle-like properties, electrons (or matter) also have wave-like and particle-like properties.

Hypothesis

 "Every moving particle has a wave associated with it".
The wavelength of moving particle is given by
𝛌=h/p
Where h is Planck's constant and p is the momentum of moving particle. Here 𝛌 represents wave nature, while momentum accounts for the particle nature. Thus the dual nature (i.e particle and wave nature) of matter was proposed by De-Broglie and it was experimentally verified by Davisson and Germer.

Matter Wave

The wave associated with moving particle is known as matter wave. Matter waves are reffered to as De-Broglie waves.

De-Broglie Wavelength

The wavelength associated with matter wave is known as De-Broglie wavelength.

Derivation
Derivation of De-Broglie relationship
De-Broglie equation.

De-Broglie relationship
De-Broglie equation.



Conclusion

De-Broglie concluded that most particles are too heavy to observe their wave properties. When the mass of an object is very small, however, the wave properties can be detected experimentally.

Questions on De-Broglie hypothesis

Q1) What is De-Broglie Hypothesis?
Ans)Every moving particle has a wave associated with it.
Q2) What is matter wave?
Ans)The wave associated with moving particle is known as matter wave. Matter waves are reffered to as De-Broglie waves.
Q3) What is De-Broglie wavelength?
Ans)The wavelength associated with matter wave is known as De-Broglie wavelength.
Q4) What is De-Broglie equation?
Ans) De-Broglie equation is given below;
𝛌=h/p.
Q5) Fill in the blanks;
1)De-Broglie concluded that most particles are too -------- to observe their wave properties.
2)When the mass of an object is very -----, however, the wave properties can be detected experimentally.
3)Matter waves are reffered to as ------ waves.
4)The dual nature (i.e particle and wave nature) of matter was proposed by --------.
5)The wavelength of moving particle is given by
𝛌=h/p
Where h is Planck's constant and p is the momentum of moving particle. Here 𝛌 represents wave nature, while momentum accounts for the --------- nature. 
6)De-Broglie, in his 1924 PhD thesis, proposed that just as light has both wave-like and particle-like properties, -------- also have wave-like and particle-like properties.
Ans)1)De-Broglie concluded that most particles are too heavy to observe their wave properties.
2)When the mass of an object is very small, however, the wave properties can be detected experimentally.
3)Matter waves are reffered to as De-Broglie waves.
4)The dual nature (i.e particle and wave nature) of matter was proposed by De-Broglie .
5)The wavelength of moving particle is given by
𝛌=h/p
Where h is Planck's constant and p is the momentum of moving particle. Here 𝛌 represents wave nature, while momentum accounts for the particle nature. 
6)De-Broglie, in his 1924 PhD thesis, proposed that just as light has both wave-like and particle-like properties, electron also have wave-like and particle-like properties.

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