PASCO ET-8782 Energy Transfer– Thermoelectric - Manual (Page 24)

Energy Transfer –Thermoelectric Teachers’ Notes–Load Resistance and Efficiency
24 ®
6) Theoretically P = 0 when R
L
= 0. Experimentally this was not the case.
7)
8) Experimental data with curve fit:
R
L
(W)
P
(W)
Max P when
R
L
= R
i
Theoretical P vs. R
L
(with arbitrary values)
V
NL
= 10 V
R
i
= 5 Ω
P
V
NL
2
R
L
R
T
+
( )
R
i
R
L
R
T
+ +
( ) 2
-------------------------------------- =
R
L
(W)
P
(W)
V
NL
= 1.49 ± 0.1 V
R
i
= 7.4 ± 0.1
Ω
R
T
= 0.90 ± 0.04 Ω
Root MSE = 0.011 W