Physics people, I love you.

<p>Well, I WILL love you.</p>

<p>I have a lab on resistance in a conductor. Basically, we measured resistance in a nichrome wire while increasing the length. Anyhow, I can answer most of the lab questions, but there're a couple that I'm confused on. The first is... My calculated restivity is about half that of the accepted value. Since nichrome is an alloy, I'm thinking composition makes a difference. But is there anything else I'm missing?</p>

<p>Second question is... Since a battery has internal resistance, does the voltage across it differ from the voltage across a resistor attached to it? Or, how's the voltage across a resistor different from the voltage across the battery itself?</p>

<p>Any hints and random bits of knowledge are welcome.</p>

<p>I suck at physics, I know.</p>