(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

The standard kilogram is a platinum-iridium cylinder 39.0 mm in height and 39.0 mm in diameter. What is the density of the material?

2. Relevant equations

now I know that to find volume you have to use v=h(pi)r^2

and I also know you have to convert it to meters. When I do I get this

(0.039)(pi)(0.0195)^2

which gives me 4.6589033654573236278091385713189e-5

so this is what I get over all

1 / (39.0 * pi * (19.5^2)) = 2.14642786 × 10-5

yet the answer is 2.15*10^4k/m^3

can someone tell me what im doing wrong, and if im suppose to convert the 2.14

3. The attempt at a solution

**Physics Forums | Science Articles, Homework Help, Discussion**

Dismiss Notice

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Homework Help: Density of a platinum-iridium cylinder

**Physics Forums | Science Articles, Homework Help, Discussion**