# Homework Help: Resistance of a wire

1. Feb 27, 2012

### john216

1. The problem statement, all variables and given/known data

Suppose that a 32-meter length of resistive wire is connected across the terminals of a battery. If a voltmeter reads 21 V when connected across the battery terminals, what should it read when connected across a 18-meter section of the wire? Enter you answers using one decimal place, do not enter units.

2. Relevant equations

e = iR

3. The attempt at a solution

thought the voltage doesn't change.

2. Feb 27, 2012

### SammyS

Staff Emeritus
Hello john216. Welcome to PF !

Think of this as 32 one-meter lengths of wire connected in series.

What is the voltage drop across any one of those one-meter wires ?

How much across 18 of them ?

3. Feb 27, 2012

### john216

could you clarify little?
i'm confused

4. Feb 28, 2012

### SammyS

Staff Emeritus
It's hard for me to know what part/parts of what I posted confuses you.

What do you understand about series circuits and resistances in series?

What do you understand about voltage drop and Ohm's Law?

etc.