PDA

View Full Version : PLEASE HELP Unit conversion (Volume, Mass, Density)


Amil
Sep13-04, 07:01 PM
My first week of class and I'm just tied up with this problem. I must be missing something.
Question:
A cylindrical swimming pool is 132 cm high and 365 cm in diameter. What will be the volume (in liters) of water neccessary to fill this pool, knowing that one cubic decimeter is equal to one liter? Supposing that the desity of water is 1.0g/cm3, what will be the mass of water in this pool?

I calculated that the cylinder has a volume of 1.380 x 10^7 cm^3 (13804774.5 cm^2) using the pi x r^2 x h formula. But what next?

Thanks in advance for any help. I really need to understand how to convert these types of units.

AMIL

mathman
Sep13-04, 07:07 PM
1000 cubic cm = 1 liter, so your volume is 1.380 x 104 liters. Mass in grams = volume in cubic cm.

chroot
Sep13-04, 07:51 PM
Mass in grams = volume in cubic cm.
More generally, mass = density * volume.

In the case of water, when mass is in grams and volume is in cm^3, the mass and volume are numerically identical, because water has a density of one gram per cubic centimeter. In general, however, you have to be careful.

- Warren