Matter Waves Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

Are matter waves electromagnetic? Why?

A

No, because they do not depend on whether the particle has charge or not, unlike electromagnetic waves which are only possible with charged particles.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What will be the graph between de-Broglie wavelength and momentum of a particle?

A

Rectangular, because the area under the graph must be constant as lambda*p=h which is a constant.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Name a phenomenon which proves a. Particle nature, b. Wave nature.

A

a. The photoelectric effect.

b. Interference, Davisson and Germer experiment.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Which has a greater de-Broglie wavelength: a proton or an electron with the same velocity?

A

The electron has a greater wavelength being lighter than the proton.
Lambda=h/mv

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are matter waves?

A

The waves predicted by de-Broglie that are associated with particle nature or moving particles are called matter waves.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

State the de-Broglie hypothesis.

A

Radiation is considered as having particle nature. Sometimes, moving particles act as waves as well.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Why is the wave matter of everyday objects not visible to us?

A

According to the equation lambda=h/mv,
Because the mass of everyday objects is much larger, their wavelengths are also much smaller and cannot show any visible effect.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Show that the electromagnetic radiation wavelength of a photon is equal to the de-Broglie wavelength.

A

de-Broglie wavelength of a photon is given by lambda=h/p,
Since the kinetic mass=h/clambda,
p=m
c =hc/lambda*c =h/lambda. Substituting in de-Broglie equation, we get the answer as equal to lambda.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the relation between a proton and an electron in terms of a. Wavelength, and b. Kinetic energy?

A

a. lambda is inversely proportional to root of mass. Since the mass of the electron is smaller, it has a larger wavelength.
b. lambda is inversely proportional to root of (2mK) which is a constant for each particle. Since electron mass is less than that of a proton, electrons have higher energy and thus higher velocity.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Describe what happens when moving electrons are allowed to fall on a thin graphite sheet and the emergent beams fall on a fluorescent screen.

A

A central sport (of undeflected electrons) surrounded by a series of concentric diffraction rings are obtained.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly