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S.priyadarshini
Subject: Physics
, asked on 16/5/18
how is lambda equals hc/eVo+Wo. I know that lambda equals hc/energy of photon
Answer
1
Lavneesh Rajput
Subject: Physics
, asked on 6/5/18
please explain these terms
Q.(a) :
i
2
R
t
=
W
=
J
H
Answer
2
Jeneeta Eliza John
Subject: Physics
, asked on 1/5/18
Q25. The potential energy of a particle of mass m is given by
U
(
x
)
=
E
0
,
0
≤
x
≤
1
0
,
x
>
1
λ
1
and
λ
2
are the de-Broglie wavelengths of the particle, when
0
≤
x
≤
1
and x > 1 respectively. If the total energy of the particle is
2
E
0
, the ratio
λ
1
λ
2
will be
(1) 2 : 1 (2) 1 : 1
(3)
2
: 1 (4) 1 :
2
Answer
1
Aparna Sahu
Subject: Physics
, asked on 24/4/18
Solve this:
Q.45. If the work function of a metal is 4.2 eV, the cut off wave length is
(a) 8000 Å
(b) 7000 Å
(c) 1472 Å
(d) 2950 Å
Answer
1
Aparna Sahu
Subject: Physics
, asked on 18/4/18
Q 37
when a metal with work function of 0.6 eV is illuminated with the light of 2 eV, the necessary stopping potential for the metal will be
(a) 2.6 V (b) 3.6 V
(c) 0.8 V (d) 1.4 V
Answer
1
Laieeqa
Subject: Physics
, asked on 17/4/18
Solve this:
27. What is the de Broglie wavelength of the electron accelerated through a potential difference of 100 Volt?
(1) 12.27 A (2) 1.227 A
(3) 0.1227 A (4) 0.001227 A
Answer
1
Poonam Tripathi
Subject: Physics
, asked on 10/4/18
Plz hlp me out vry urgent plz fast
Following diffaction pattern was obtained
using a diffraction grating using two
different wavelengths
λ
1
a
n
d
λ
2
. With the
help of the figure identify which is the longer
wavelength and their ratios
(
a
)
λ
1
i
s
l
o
n
g
e
r
t
h
a
n
λ
2
a
n
d
t
h
e
r
a
t
i
o
o
f
t
h
e
l
o
n
g
e
r
t
o
t
h
e
s
h
o
r
t
e
r
w
a
v
e
l
e
n
g
t
h
i
s
1
.
5
(
b
)
λ
1
i
s
l
o
n
g
e
r
t
h
a
n
λ
2
a
n
d
t
h
e
r
a
t
i
o
o
f
t
h
e
l
o
n
g
e
r
t
o
t
h
e
s
h
o
r
t
e
r
w
a
v
e
l
e
n
g
t
h
i
s
1
.
5
(
c
)
λ
1
a
n
d
λ
2
a
r
e
e
q
u
a
l
a
n
d
t
h
e
i
r
r
a
t
i
o
i
s
1
.
0
(
d
)
λ
2
i
s
l
o
n
g
e
r
t
h
a
n
λ
1
a
n
d
t
h
e
r
a
t
i
o
o
f
t
h
e
l
o
n
g
e
r
t
o
t
h
e
s
h
o
r
t
e
r
w
a
v
e
l
e
n
g
t
h
i
s
2
.
5
Answer
1
Sandali Khare
Subject: Physics
, asked on 5/4/18
A photon of wavelength λ is scattered from an electron , which was at rest .The wavelength shift △λ is three times of λ and the angle of scattering θ is 600 . The angle at which the electron recoiled is ϕ .The value of tanϕ is (electron speed is much smaller than the speed of light)
Answer
2
Aparna Sahu
Subject: Physics
, asked on 16/3/18
Solve this.
Q. The surface of a metal is illuminated with the light of 400 nm. The kinetic energy of the ejected photoelectrons was found to be 1.68 eV. The work function of the metal is
A. 1.41 eV
B. 1.51 eV
C. 1.68 eV
D. 3.09 eV
Answer
1
Aparna Sahu
Subject: Physics
, asked on 16/3/18
Solve this.
Q. Find the de-Broglie wavelength of an electron with kinetic energy of 120 eV.
A. 112 pm
B. 95 pm
C. 124 pm
D. 102 pm
Answer
1
Aparna Sahu
Subject: Physics
, asked on 16/3/18
Solve this.
Q). The de Broglie wavelength of an electron accelerated to a potential of 400 V is approximately
0.03 nm
0.04 nm
0.12 nm
0.06 nm
Answer
1
Annabeth Chase
Subject: Physics
, asked on 8/3/18
Solve this plzzz..
Q.3. In X-ray tube the potential difference between the anode and the cathode is 20 kV and current flowing is 2 mA. Find,
(a) The number of electrons striking the anode in 1 s,
(b) The speed of electrons while striking the anode,
(c) Minimum wavelength (
λ
m
i
n
) emitted.
Answer
1
Shvaetha Kumaravel
Subject: Physics
, asked on 6/3/18
How are frequency and photoelectric current related? Directly or independent?
Answer
1
Vidipta Fulpadia
Subject: Physics
, asked on 3/3/18
Solve this:
Q2. (a) Plot a graph showing the variation of stopping potential (V
0
) with frequency (
ν
) of incident radiation. find its (i) slope and intercept on the potential Axis.
(b) An electron is accelerated through a P.D of 64 volts. What is the de- Broglie wavelength associated with it. To which 220 part of electromagnetic spectrum does this correspond ?
(c) An
∝
- particle and a proton are accelerated by the same potential. Find the ratio of their de- Broglie Wavelength.
Answer
1
Ketul
Subject: Physics
, asked on 1/3/18
Do the emitted photoelectrons have the same KE?
Answer
4
1
2
3
4
5
Next
What are you looking for?
Q.(a) :
(1) 2 : 1 (2) 1 : 1
(3) : 1 (4) 1 :
Q.45. If the work function of a metal is 4.2 eV, the cut off wave length is
(a) 8000 Å
(b) 7000 Å
(c) 1472 Å
(d) 2950 Å
(a) 2.6 V (b) 3.6 V
(c) 0.8 V (d) 1.4 V
27. What is the de Broglie wavelength of the electron accelerated through a potential difference of 100 Volt?
(1) 12.27 A (2) 1.227 A
(3) 0.1227 A (4) 0.001227 A
Following diffaction pattern was obtained
using a diffraction grating using two
different wavelengths . With the
help of the figure identify which is the longer
wavelength and their ratios
Q. The surface of a metal is illuminated with the light of 400 nm. The kinetic energy of the ejected photoelectrons was found to be 1.68 eV. The work function of the metal is
A. 1.41 eV
B. 1.51 eV
C. 1.68 eV
D. 3.09 eV
Q. Find the de-Broglie wavelength of an electron with kinetic energy of 120 eV.
A. 112 pm
B. 95 pm
C. 124 pm
D. 102 pm
Q). The de Broglie wavelength of an electron accelerated to a potential of 400 V is approximately
Q.3. In X-ray tube the potential difference between the anode and the cathode is 20 kV and current flowing is 2 mA. Find,
(a) The number of electrons striking the anode in 1 s,
(b) The speed of electrons while striking the anode,
(c) Minimum wavelength () emitted.
Q2. (a) Plot a graph showing the variation of stopping potential (V0) with frequency () of incident radiation. find its (i) slope and intercept on the potential Axis.
(b) An electron is accelerated through a P.D of 64 volts. What is the de- Broglie wavelength associated with it. To which 220 part of electromagnetic spectrum does this correspond ?
(c) An - particle and a proton are accelerated by the same potential. Find the ratio of their de- Broglie Wavelength.