I cant seem to get this one, I just dont know how to calculate the effective resistance, what is the difference between effective resistance and normal resistance??(adsbygoogle = window.adsbygoogle || []).push({});

Here is the question:

A car battery has a source voltage of 12.00 V and an internal resistance of

0.015 Ω. When the headlights are turned on (while the engine is not running)

the output voltage of the battery drops to 11.75 V. The effective resistance of

the headlights is nearest to:

If someone could just give me a formula or some hints........that would be great!

**Physics Forums | Science Articles, Homework Help, Discussion**

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Homework Help: Effective resistance Question

**Physics Forums | Science Articles, Homework Help, Discussion**