# Mass of grain of sand

#### scc

1. Homework Statement
Fine grains of beach sand are assumed to be spheres of radius 38.1 micro meters (can't figure out the scientific sign). These grains are made of silicon dioxide which has a density of 2600 kilograms/meters^3. What is the mass in kg?

2. Homework Equations

3. The Attempt at a Solution
I input 3 different answers and they're all wrong (603.2 kg and others near that - I know I'm way off). I'm not sure at all how to calculate. Please help!

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#### Borek

Mentor
Show how you got your answers, it is hard to help not knowing what you are doing wrong.

#### whatsoever

Since you don't tell how you got 603.2kg, I tried guessing where you went wrong... and I guess
that when you convert the density from kg/m3 to kg/$$\mu$$m3, you multiplied it by 10-6 when you are supposed to multiply it by (10-6)3

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