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Unit conversions

  • #1

Homework Statement


A block of wood measuring 5 cm x 3 cm x 10 cm has a mass of 90 grams. What is the density of the wood in kg/m^3?

Homework Equations


D=m/V

The Attempt at a Solution


I know this seems trivial but I need to get the math down to a T. I know that it s 06.g/cm^3 but how is this converted to kg/m^3? For example, we know that 1 m^3 = 10^6 cm^3. My calculation are as follows:

(0.6 g/cm^3)(1 kg/1000g)(100000 cm^3/1 m^3). I keep getting 60 kg/m^3 but the correct answer is 6.0 x 10^2 kg/m^3. Seriously, what am I continually doing wrong? Thanks for the help!
 

Answers and Replies

  • #2
SammyS
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Homework Statement


A block of wood measuring 5 cm x 3 cm x 10 cm has a mass of 90 grams. What is the density of the wood in kg/m^3?

Homework Equations


D=m/V

The Attempt at a Solution


I know this seems trivial but I need to get the math down to a T. I know that it s 06.g/cm^3 but how is this converted to kg/m^3? For example, we know that 1 m^3 = 10^6 cm^3. My calculation are as follows:

(0.6 g/cm^3)(1 kg/1000g)(100000 cm^3/1 m^3). I keep getting 60 kg/m^3 but the correct answer is 6.0 x 10^2 kg/m^3. Seriously, what am I continually doing wrong? Thanks for the help!
count the zeros in 100000 cm3/1 m3 . It's wrong.
 
  • #3
I am getting conflicting information from my book and from online sources! My book states that 10^6 cm^3 = 1 m^3. ??
 
  • #4
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I am getting conflicting information from my book and from online sources! My book states that 10^6 cm^3 = 1 m^3. ??
Which are how many zeros?
 
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  • #5
Wow. Can't believe I missed that! Thanks for catching my careless error!!
 
  • #6
berkeman
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Don't bother memorizing that conversion. Just write it like this: 1 = (100cm/m)^3
 
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