Young's Double Slit
experiment
same 1 andf
-
For interference need coherentsources.
pattern to occur
you I
constant phase difference
lightfrom the slits
ont
acts
like two coherent sources
↓
allows to have a
bulb single wavelength
Laser is coherentand
monochromatic (the same
wavelength)
(p.d 21 Precautions when las
working with
=
a
(p.d 0)
=
1. Do lookdirectly
not the
at laser beam
Wear
2. laser
safety goggles
3. Turn the laser off when needed
not
sproved thatlightis a wavel
4. Have
warning sign.
fromthe
distance
w
e
=
S
s1:Iseparation
↓
E
fringe spacing
Blue
light is usedinstead red
of
light?
Blue
light smaller 1 =>
Whispots further apart)
-
, Single slit
acts as a
single source
diffracting
both
light to sides. Itallows to have a
single
wavelength
After
passing through
slits
lightspreads and
out then
the waves meet.
Superposition occurs and the interference
be seen. formedatthe of
pattern can
Brightfringes are
points
constructive interference where two waves
in
meet
phase (p.d=nx)
Diffraction
Diffraction when waves
spread as they go through a
-
out
narrow obstacles.
gap round
or
the of
amount diffraction depends on the
wavelength.
1) When lot
bigger then the 1, diffraction unnoticeable.
gap
a is a is
2) The most diffraction when the
gap
is the same size as the
wavelength.
If have
you no trouble
hearing someone
through as
open door to the room
next (sound 1:gap siz
can't
but them the door
see
(light-gap size of
3) Ifthe gap is smaller that the
wavelength, the waves back.
reflect
experiment
same 1 andf
-
For interference need coherentsources.
pattern to occur
you I
constant phase difference
lightfrom the slits
ont
acts
like two coherent sources
↓
allows to have a
bulb single wavelength
Laser is coherentand
monochromatic (the same
wavelength)
(p.d 21 Precautions when las
working with
=
a
(p.d 0)
=
1. Do lookdirectly
not the
at laser beam
Wear
2. laser
safety goggles
3. Turn the laser off when needed
not
sproved thatlightis a wavel
4. Have
warning sign.
fromthe
distance
w
e
=
S
s1:Iseparation
↓
E
fringe spacing
Blue
light is usedinstead red
of
light?
Blue
light smaller 1 =>
Whispots further apart)
-
, Single slit
acts as a
single source
diffracting
both
light to sides. Itallows to have a
single
wavelength
After
passing through
slits
lightspreads and
out then
the waves meet.
Superposition occurs and the interference
be seen. formedatthe of
pattern can
Brightfringes are
points
constructive interference where two waves
in
meet
phase (p.d=nx)
Diffraction
Diffraction when waves
spread as they go through a
-
out
narrow obstacles.
gap round
or
the of
amount diffraction depends on the
wavelength.
1) When lot
bigger then the 1, diffraction unnoticeable.
gap
a is a is
2) The most diffraction when the
gap
is the same size as the
wavelength.
If have
you no trouble
hearing someone
through as
open door to the room
next (sound 1:gap siz
can't
but them the door
see
(light-gap size of
3) Ifthe gap is smaller that the
wavelength, the waves back.
reflect