Go Back   Physics Help Forum > High School and Pre-University Physics Help > Light and Optics

Light and Optics Light and Optics Physics Help Forum

Reply
 
LinkBack Thread Tools Display Modes
Old Sep 1st 2013, 11:20 PM   #1
Junior Member
 
Join Date: Sep 2013
Posts: 2
Question wat actually does wavelength means?

Hello
Dear people,i wanted to know wat actually is wavelength??
I have heard all the definations most of them says its difference
bw two crest or trough..that is ok.most of the people understand
wavelength as path of particles while travelling..is it true??
ankit29030 is offline   Reply With Quote
Old Sep 2nd 2013, 04:42 AM   #2
MBW
Senior Member
 
MBW's Avatar
 
Join Date: Apr 2008
Location: Bedford, England
Posts: 668
Wavelength can apply to many different physical processes.
For each of these processes an analogy has been made between the actual physical process and a wave as might be seen in water.
Most of the processes in physics that generate a wave are generated by something oscillating (swinging back and forth).
Consider a ball on a spring bouncing up and down,
Now lower this so that the ball just dips in and out of a pond,
this will generate a series of waves.
The frequency of the waves is set by the bounce rate of the ball on the spring,
the speed of the waves is set by the properties of water,
the wavelength (which as you correctly observe) is measured between corresponding points on consecutive waves
mathematically the wavelength can be determined from the frequency and the speed:
wavelength = speed / frequency

When physicists talk about the wavelength of a particle, the analogy is being streached rather a long way...

Last edited by MBW; Sep 2nd 2013 at 04:49 AM. Reason: spelling
MBW is offline   Reply With Quote
Old Sep 2nd 2013, 05:00 AM   #3
Junior Member
 
Join Date: Sep 2013
Posts: 2
sir wat does wavelength of electron means...??? how does shorter wavelength of electrons help in more magnification in an electron microscope rather than optical microscope as photons with greater wavelength??

Last edited by ankit29030; Sep 2nd 2013 at 05:04 AM.
ankit29030 is offline   Reply With Quote
Old Sep 2nd 2013, 09:15 AM   #4
MBW
Senior Member
 
MBW's Avatar
 
Join Date: Apr 2008
Location: Bedford, England
Posts: 668
For any microscope (optical or electron) one of the key limits to the resolution
(the smallest detail that can be "seen")
is the "diffraction limit", which is a function of wavelength.

The shorter the wavelength the smaller the diffraction limit.

The effective wavelength of an electron is considerably smaller than the wavelength of visible light.

I am deliberately ignoring the question of "what does wavelength of electron mean"
that is probably at or beyond the edge of my understanding.

Anyone else out there want to have a go at it?

Last edited by MBW; Sep 2nd 2013 at 09:18 AM.
MBW is offline   Reply With Quote
Old Sep 6th 2013, 05:24 AM   #5
MBW
Senior Member
 
MBW's Avatar
 
Join Date: Apr 2008
Location: Bedford, England
Posts: 668
Exclamation This is MY theory (ahem)

Ok so no-one else volunteered to explain particle-wave duality (chickens),
so I will barge in where others are too sensible to tread.
NOTE: THIS IS MY INTERPRETATION based on a little knowledge (always a dangerous thing)
I definitely DONT hold this up as the proper "scientific" explanation.

A particle (such as an electron) has a probability of interacting with each (and every one) of the other particles in the universe.
With some pairs of particles interaction is quite likely, with others it is rather unlikely (this could be taken as one definition of distance).

When the particles are moving relative to each other the probability of their mutual interaction takes on a wave like character with the probability of interaction varying in an oscillatory fashion with particle position.

Ok let's see if this prods someone to correct me, and give a "better" definition of wave-particle duality...
MBW is offline   Reply With Quote
Reply

  Physics Help Forum > High School and Pre-University Physics Help > Light and Optics

Tags
means, wat, wavelength



Thread Tools
Display Modes


Similar Physics Forum Discussions
Thread Thread Starter Forum Replies Last Post
What temperature actually means? kelsiu Thermodynamics and Fluid Mechanics 5 Apr 23rd 2015 12:10 PM
Frequency and Wavelength muon321 Quantum Physics 3 Mar 5th 2013 09:46 PM
Could you please tell me what in laymanís terms normalisation of EMG means waynesplash Kinematics and Dynamics 0 Dec 16th 2011 03:12 PM
Calculating wavelength elieh Waves and Sound 4 Mar 16th 2011 08:02 AM


Facebook Twitter Google+ RSS Feed