Having a problem with a fairly early Physics with Calculus 1 problem

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Homework Help Overview

The problem involves calculating the area of a gold leaf and the length of a cylindrical fiber made from gold, utilizing concepts from physics and calculus. The context includes unit conversions and volume calculations based on the properties of gold.

Discussion Character

  • Exploratory, Conceptual clarification, Mathematical reasoning

Approaches and Questions Raised

  • The original poster attempts to solve part (a) of the problem and seeks guidance for part (b), questioning whether additional information is needed or if unit conversions are sufficient. Some participants suggest calculating the mass and volume of gold, while others reference the formula for the volume of a cylinder to find the length of the fiber.

Discussion Status

The discussion includes attempts to clarify the approach to part (b) of the problem, with participants offering hints and suggestions for calculating the length of the fiber based on the volume of gold and the given radius. There is no explicit consensus, but several productive directions have been proposed.

Contextual Notes

The original poster indicates uncertainty about the calculations and whether they have made errors in their previous work. The problem involves specific measurements and conversions that are critical to the calculations.

frankfjf
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Hi all, been a while since I posted here needing homework help but it's a new semester and I'm already stumped (much to my shame :shy: ) Anyway, I am presented with the following problem:

Gold, which has a mass of 19.32 g for each cubic centimeter of volume, is the most ductile metal and can be pressed into a thin leaf or drawn out into a long fiber. (a) If 9.000 oz of gold, with a mass of 27.63 g/oz, is pressed into a leaf of 1.000 mm thickness, what is the area (in m^2) of the leaf? (b) If, instead, the gold is drawn out into a cylindrical fiber of radius 2.900 mm, what is the length (in m) of the fiber?

I have already solved part a, but am uncertain how one solves part b? I just need a hint or two to get started on the right direction. Do I just convert the units accordingly or do I need to obtain more information first? I was able to solve part a by simply converting the 9 oz. of gold into cubic centimeters using the information given and then further converting from there, but that doesn't seem to work for part b, unless I did my math wrong somewhere. Please help! Thanks!
 
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Still stumped... can't anyone help?
 
find the mass of the gold, and change it into volume. now divide this volume by the cross section area of the wire. make sure to use the right units.
 
The formula for a volume of a cylinder is V=pi*r2*L. Since you have already calculated the volume of gold (V), and are given the radius (r), it should be simple to find the length of the fiber (L).
 
Thanks for your help!
 

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