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Ch.1 - Introduction: Matter, Energy, and Measurement
Chapter 1, Problem 83

A thief plans to steal a cylindrical platinum medal with a radius of 2.3 cm and a thickness of 0.8 cm from a jewellery store. If the platinum has a density of 21.45 g/cm³, what is the mass of the medal in kg? [The volume of a cylinder is V = πr²h.]

Verified step by step guidance
1
Calculate the volume of the cylindrical medal using the formula for the volume of a cylinder: \( V = \pi r^2 h \), where \( r \) is the radius and \( h \) is the thickness.
Substitute the given values into the volume formula: \( r = 2.3 \text{ cm} \) and \( h = 0.8 \text{ cm} \).
Compute the volume \( V \) in cubic centimeters (cm³) using the substituted values.
Use the density formula \( \text{Density} = \frac{\text{Mass}}{\text{Volume}} \) to find the mass. Rearrange it to \( \text{Mass} = \text{Density} \times \text{Volume} \).
Substitute the calculated volume and the given density (21.45 g/cm³) into the mass formula to find the mass in grams, then convert the mass from grams to kilograms by dividing by 1000.