BAI TAP LUONG TU ANH SANG PHAN 4

BT về lượng tử ánh sáng P - 4
Câu 16: !"#$%&
'( "#)*+,-&./&%0%12(hiệu suất của sự phát quang là tỉ số giữa
năng lượng của ánh sáng phát quang và năng lượng của ánh sáng kích thích trong một đơn vị thời gian)3
44-&+5+6%767)6
6 
8)9344-&:#/&
&6%
A. 7(!7;)6
67
B. 7 6 )6
6<
C. 6<=!6)6
6<
D. 71!;)6
66
Giải>4-&?@
λ
hc
@344-&&6)
4-&/&>)?'@'
A
λ
hc
@'344-&/&&6)
B,-&./&>B
A
AA
λ
λ
N

N
P
P
=
CCCCCCD@'@B
λ
λ
A
767)6
6
)1)
!
( 
7 6 )6
6<
)Chọn đáp án B
Câu 17&3-&+%/&5,E4%#F##8G8/&5,λ


(µ#)+$%&3λ=µ#)H3I%##8G3
6#)JK&L#F,5,+6M)NOP#Q&3/&5R
>H)S (##*)S (#)S!6##T)S(7#
Giải /&U&&3$R3&5V.58$
#&
5W5X4UH&
$P,W/&5,>

7
7
#&


mv
hchc
+=
λλ
CCCCCCD
=
(<6
!<

#&

7
#&
6)!<
6)=)(
Y=(Z
6)61
6)<)6)(7=()7
Y
66
Z
7
Y
66
Z
7
=
−
=−=⇒−=

−−
−
λλλλ
m
hc
vhc
mv
Z#[Y
/&U&&3&$%0\5F$P&35/&&0
&$#QG&3]^&_V%:-&#Q`S
#&

%V#&0&-&/&%0>S
#&
$
#&
$%a&0\5F-&/&bc5+
Hd.eO5Ffgh[e#&$&%&3-&/&)
e&
7
[7) J&3-&/&0\5Fbc$PH
&h
Hc
[#e)a&0\5F-&bc$PH

!
61
<67
6)(;6
6)6)(6

66)61)777
−
−
−−
===
AK
eU
md
a
d
ZY
R
max
= v
0max
t = 3,8.10
5
.1,067.10
-8
= 4,0546.10
-3
m
= 4,06 mm. Chọn đáp án A
Câu 18>&5,.i&5QV&E4$%
5W3$65,5,e!f)+$%675,.$a&5-Ei
V36
6=
Bj5+e`/&5,#%%)4_&%H
7;(7=M)5,/OkeViZl3>66)6
C!

Y
Giải: Hmh

CCCCCD h

nH((7=)6
C<
)6
6=

61
6)(6
6
−
C7;(7=ZMY
 6 (n7;(7=ZMY6<;!6ZMYCCCCDh

6<;!6ZMY
l,/OkeViq = CU
h
= 1,3781.8.10
-9
= 1,1. 10
-8
C.
Câu 19>N#o0Op*0Op540\5F-&O/&8E%
0\5F`5P)Nq3K&35F-&OO/r58c$%35F-&OO/r58s
i
H)1)*)7))<)T) )
e

S
$
#&
c
H
Giải:
t5E&\UO#V04eo+O##k#^u
Giải>cO0\5F/&8E%0\5F`5P)v.4^K&
O$%8E5$&`%.E#O&>

r
mv
7

7
7
r
e
CCCCCCCD$
7

mr
ke
7
)CCCCCCCD
7
YZ
M
K
v

v

K
M
r
r
1CCCCCCCD
M
K
v
v
<)Chọn đáp án C
Câu 20:sF3S^C85Fe5,
VU ==
)c5a5Fe`5,/&3
S^C%
mAI ==
)Jk+62wW-&chïm5W0\&%wW-&
&x$%wWv-&&x&i;=2wW-&&y)
*+&&$$R4i)N3-&&x&6E0z
A.3,125.10
16
(ph«t«n/s) B.3,125.10
15
(ph«t«n/s)
C.4,2.10
15
(ph«t«n/s) D.4,2.10
14
(ph«t«n/s)

Giải:
@wW&&xi5W4U>
ε
#&

#
λ
hc

7
7
mv
h
@wWv-&&x>ε
x
;=ε
#&
;=h
J{%3-&&x&64-&:#&x>
?ε
x
;=h
935+5W&6>


e
I
)@wW:#5+&6%
?




7
7
mv

e
I
h|h
N%&>?6?

CCCCCCCD;=h6|h
CCCCCD
e
I
);=
6

61
<
6)(6));=
6)=)6
−
−
4,166.10
14
= 4,2.10
14
(photon/s). Chọn đáp án D