Question

An automobile battery, when connected to a car radio, provides 12.5 V to the radio. When connected to a set of headlights, it provides 11.7 V to the headlights. Assume the radio can be modeled as a 6.4? resistor and the headlights can be modeled as a 0.55? resistor.Part A - vth = 12.6VPart BWhat is the Thevenin equivalent resistance for the battery?Part CWhat is the Norton equivalent current for the battery?Part DWhat is the Norton equivalent resistance for the battery?

Answer 1

Base on the question, and in my further computation, the possible answers would be the following and I hope you are satisfied with my answer and feel free to ask for more.

- If you want to determine the Thevenin equivalent voltage and resistance without overloading the battery, then apply some known resistance 

RLRL and measure the output voltage as VLVL. Measure the voltage without a load as VOCVOC. The voltage divider equation tells us that

VL=VOCRLRTH×RLVL=VOCRLRTH×RL

Solve for RTHRTH, and you know that VTH=VOCVTH=VOC.