Lab 6: Maximum Power Transfer

Intro:

The purpose of this lab is to experimentally verify the Maxumum Power Transfer Theorem.

P=(V_th /(R_th + R_L)² *R_L

Power maximum when R_th = R_L

Experiment and Data:

Part A

Data part A

Vo(volts)	Rx(ohms)	Power(mW)
0.015	120	0.001875
0.037	712	0.00192275
0.045	1220	0.00165984
0.069	1890	0.00251905
0.076	2160	0.00267407
0.09	2590	0.00312741
0.117	3590	0.00381309
0.132	4310	0.00404269
0.166	5150	0.00535068
0.165	5730	0.00475131
0.176	6370	0.00486279
0.19	7150	0.00504895
0.219	8940	0.00536477
0.243	10770	0.00548273
0.251	11360	0.00554586

Analysis

Max power was at around 5.15k ohms.  The theoretical resistance of max power is when the load resistance equals the thevenin resistance.  Since the thevenin resistance is 5.6k ohms the, the load resistance of max power is 5.6k ohms.  The percent error is 8.04%

Part B

We tried to use LoggerPro to find the thevenin resistance, but the program did not work. There was too much noise in the measuring devices.