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Mass and Volume = Density

So I know that Mass divided by Volume = Density

But, how do I get my answer? Am I using a calculator?

650g divided by 922cm^3 =

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Reply 1
Turn 650g into kg. Turn 922cm^3 into meters. Then divide.

cm = 10^-2
g = 10^-3
(edited 9 years ago)
Reply 2
Yes, using a calculator would probably help.
Reply 3
how can I turn the last one into metres?
Imagine a box in the shape of a cube of length 1 m
It's volume would be 1 x 1 x 1 = 1 m^3
1 m equal 100 cm
So the same volume would be 100 x 100 x 100 cm^3
To convert your volume to m^3 divide it by 1000000

Although the standard units for density are kg/m^3 There is probably no need to change the units of your calculation
You only need to do that if the units in the information don't match the units of the required answer.
Density = mass / volume
Use a calculator
The units of your answer will g/cm^3 (g cm^-3)

Does your question specify what density units you are required to use? Or are you doing a course of study that requires all units to be SI units?

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(edited 9 years ago)
Reply 5
Original post by gdunne42
Imagine a box in the shape of a cube of length 1 m
It's volume would be 1 x 1 x 1 = 1 m^3
1 m equal 100 cm
So the same volume would be 100 x 100 x 100 cm^3
To convert your volume to m^3 divide it by 1000000

Although the standard units for density are kg/m^3 There is probably no need to change the units of your calculation
You only need to do that if the units in the information don't match the units of the required answer.
Density = mass / volume
Use a calculator
The units of your answer will g/cm^3 (g cm^-3)


the answer I got for the above question is =

1.22107703354
is this correct?
Original post by fliss1992
the answer I got for the above question is =

1.22107703354
is this correct?


650÷9221.22107703354650 \div 922 \neq 1.22107703354

You need to state your units anyway.

What did you type into your calculator to get that number?
(edited 9 years ago)
Reply 7
650g divided by 922cm^3 = 1.22107703354g/cm^3

that's what I calculated and that's the answer I got above..
Unless your calculator is broken.........
No you didn't



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Original post by fliss1992
650g divided by 922cm^3 = 1.22107703354g/cm^3

that's what I calculated and that's the answer I got above..


The units are ok now.

I'm pretty sure you are not a troll so you must just be out of your depth. May I ask what grade you got in GCSE maths? I apologise if I have asked you this before.
(edited 9 years ago)
Reply 10
I haven't done GCSE Maths, I am studying at the moment and haven't done much on anything covered in the GCSE, so it's all new.

You say the units are ok now, is the answer correct?

As the above person doesn't agree?
Density is measured in or Kg per metre cubed.

So divide the volume by 1000 to get metres cubed.
Divide grams by 1000 to get kilograms.
then use the formula mass/volume=density
Original post by fliss1992
650g divided by 922cm^3 = 1.22107703354g/cm^3

that's what I calculated and that's the answer I got above..


:banghead::banghead::banghead::banghead::banghead:

a number divided by a number greater than it, is always lesser than "1".

the correct answer is something like 0.7xxxxxx
Reply 13
Original post by SamTheMan95
Density is measured in or Kg per metre cubed.

So divide the volume by 1000 to get metres cubed.
Divide grams by 1000 to get kilograms.
then use the formula mass/volume=density


Now I have 0.70498915401 g/cm^3
Original post by SamTheMan95
Density is measured in or Kg per metre cubed.

So divide the volume by 1000 to get metres cubed.
Divide grams by 1000 to get kilograms.
then use the formula mass/volume=density


Firstly, although the SI Unit of density is kg/m^3
- g/cm^3 would be an acceptable unit in most circumstances
- dividing cm^3 by 1000 will not convert to m^3


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Reply 15
I don't mean to be rude to anyone, and I do appreciate everyone's help but can someone please advise me on the right way to calculate this?

I followed the way Samtheman mentioned however nobody has said if my answer is correct or not?
Original post by fliss1992
Now I have 0.70498915401 g/cm^3


Correct

In most situations you would then round that answer to a suitable degree of accuracy but that's another topic for another time.


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Reply 17
OK, that's great thanks for your time and patience.

If you don't mind, I have a few more questions that are similar.

Can I post my answers and then you say if there right or wrong?
Original post by fliss1992
OK, that's great thanks for your time and patience.

If you don't mind, I have a few more questions that are similar.

Can I post my answers and then you say if there right or wrong?


You can but my advice remains the same. The order in which you are tackling these topics is not helping you. You need to master the basics first and then questions like this will start to make more sense. If you send me a private message with your postal address I will send you a MathsWatch CD. Work through this in grade order and you will start to improve.
Reply 19
Here are my next questions if someone could tell me if they are correct or not, if not can someone advise where I have gone wrong.

Thanks..

a) Weight 150g Volume 840cm^3 = 0.17857142857 g/cm^3

b) Weight 1kg Volume 125cm^3 = 8 g/cm^3

c) Weight 2kg Volume 1700 ^3 = 1.17647058824 g/cm^3

d) Weight 200g Volume 10cm^3 = 20 g/cm^3

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