Andrew's git
/
notes.git
/ diff
summary
|
log
|
commit
| diff |
tree
commit
grep
author
committer
pickaxe
?
re
refine light & matter cheatsheet
author
Andrew Lorimer
<andrew@lorimer.id.au>
Tue, 4 Sep 2018 06:50:05 +0000
(16:50 +1000)
committer
Andrew Lorimer
<andrew@lorimer.id.au>
Tue, 4 Sep 2018 06:50:05 +0000
(16:50 +1000)
physics/light-matter-ref.md
patch
|
blob
|
history
raw
|
patch
|
inline
| side by side (parent:
79b0d7a
)
diff --git
a/physics/light-matter-ref.md
b/physics/light-matter-ref.md
index 170d6a4727a09a831458353a3db0a148a3d15d3e..c0488911067fbce8879b371a6c15bffb4b2b6fd4 100644
(file)
--- a/
physics/light-matter-ref.md
+++ b/
physics/light-matter-ref.md
@@
-16,7
+16,9
@@
$$f={c \over \lambda}$$
$$E=hf={hc \over \lambda}$$
$$E=hf={hc \over \lambda}$$
-$$h=6.63 \times 10^{-34}\operatorname{J s}=4.12 \times 10^{-15} \operatorname{eV s}$$
+$$h=6.63 \times 10^{-34}\operatorname{J s}=4.14 \times 10^{-15} \operatorname{eV s}$$
+
+$$ 1 \operatorname{eV} = 1.6 \times 10^{-19} \operatorname{J}$$
## Force of electrons
## Force of electrons
@@
-28,6
+30,7
@@
$$F=evB$$
- if $V_{\operatorname{supply}} > 0$, e- are attracted to collector anode
- if $V_{\operatorname{supply}} < 0$, e- are attracted to illuminated cathode, and $I\rightarrow 0$
- $v$ of e- depends on ionisation energy (shell)
- if $V_{\operatorname{supply}} > 0$, e- are attracted to collector anode
- if $V_{\operatorname{supply}} < 0$, e- are attracted to illuminated cathode, and $I\rightarrow 0$
- $v$ of e- depends on ionisation energy (shell)
+- max current depends on intensity
### Threshold frequency
- *threshold frequency* $f_0$ - minimum frequency for photoelectrons to be ejected
### Threshold frequency
- *threshold frequency* $f_0$ - minimum frequency for photoelectrons to be ejected
@@
-45,13
+48,15
@@
$$\phi=hf_0$$
$$E_{\operatorname{k-max}}=hf - \phi$$
$$E_{\operatorname{k-max}}=hf - \phi$$
-voltage in circuit = max $E_K$ in eV
+voltage in circuit or stopping voltage = max $E_K$ in eV
+equal to $x$-intercept of volts vs current graph (in eV)
### Stopping potential
_Smallest voltage to achieve minimum current_
### Stopping potential
_Smallest voltage to achieve minimum current_
-$$V_0 = {E_{K \operatorname{max}} \over q_e} = {{hf - \phi} \over q_e}$$
+<!-- $$V_0 = {E_{K \operatorname{max}} \over q_e} = {{hf - \phi} \over q_e}$$ -->
+$$V=h_{\text{eV}}(f-f_0)$$
## De Broglie's theory
## De Broglie's theory