AS Level Physics: Resistance Help

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To calculate the voltage drop along a 4 m copper cable carrying 100 A, the resistance equation considering length, cross-sectional area, and resistivity of copper is essential. The voltage drop can be determined using Ohm's Law, where voltage equals current multiplied by resistance. The discussion highlights that using multiple strands of thin copper wire instead of a single thick wire enhances flexibility and ease of handling. This practical approach addresses issues of stiffness and allows for easier manipulation of the cables. Understanding these concepts is crucial for AS Level Physics students tackling resistance-related problems.
CathyLou
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Hiya.

I'm currently studying AS Level Physics and I've no idea how to start the following question.

Any help would be really appreciated.

‘Jump leads’ may be used for starting the engine of one car using the battery of another car. One such set of leads is 4 m long, and consists of copper cables with a cross-sectional area of 13.6 mm^2.

(a) What is the voltage drop along the length of one of these cables when it is carrying a current of 100 A?

(b) In practice, such cables are made up of a number of strands of thin copper wire rather than a single strand of thicker wire. Why?

Thank you.

Cathy
 
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What equation for resistance? (Hint, length, cross-sectional area, and resistivity of copper are important)
 
After figuring out part a using drpizza's hint--part b has little to do with physics, it's a practical usage issue.
 
As for part b.

One solid 13.6 mm wire, is fairly stiff sooo
 

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