PASCO TD-8564 THERMAL EFFICIENCY APPARATUS - Manual (Page 27)

012-05443A Thermal Efficiency Apparatus
23
➅ Calculate the power input to the hot side, P
H
= I
H
V
H
, and the power dissipated by the load
resistor, P
L
=
V
W
2
R
. Calculate the efficiency, e =
P
L
P
H
. Record all these values in Table 5.1.
➆
Adjust the power input to the hot side to keep the temperature of the hot reservoir at the
same temperature as it was for the 0.5
Ω
resistor while Steps 1 through 6 are repeated for the
other possible load resistances: 1, 1.5, 2, 2.5, 3, and 3.5 ohms.
Questions
➀ For which load resistor is the efficiency a maximum?
➁
If you have done experiment 2: How does the load resistance for optimum efficiency
compare with the internal resistance measured in that experiment?