Solving Resistance of a Wire: 21V Across 32m, 18m?

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A 32-meter length of resistive wire connected to a battery reads 21 V across its terminals. The discussion revolves around determining the voltage across an 18-meter section of this wire. Participants emphasize understanding the principles of series circuits and Ohm's Law, particularly how voltage drops across resistive segments. The key question is how to calculate the voltage drop across any given length of wire in relation to the total length. Clarification on these concepts is sought to solve the problem accurately.
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Homework Statement




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.



Homework Equations



e = iR


The Attempt at a Solution



thought the voltage doesn't change.
but I think its wrong. Please help?
 
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john216 said:

Homework Statement



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.

Homework Equations



e = iR

The Attempt at a Solution



thought the voltage doesn't change.
but I think its wrong. Please help?
Hello john216. Welcome to PF !

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

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

How much across 18 of them ?
 
could you clarify little?
i'm confused
 
john216 said:
could you clarify little?
I'm confused
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.
 

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