Density = mass/volume The unit for density is kg/cubic metre, written as kg m-3, where the -3 is superscript, written at the top right of the m.To find mass, use a balance. To convert g to kg, divide by 1000.To find the volume of an irregular shape, e.g. a stone, find out the volume of water it displaces. An object will displace a volume of water equal to its own volume. You can use an eureka can if there's one to hand, or for a simple method, use a measuring cylinder marked with 1mm graduations. Fill the cylinder with water to a depth which will cover the stone, e.g. 500 ml. Place the stone into the water and note the new level of the water. Since 1ml = 1 cm cubed, the original water volume subtracted from the new volume will give the volume of the stone in cm cubed. E.g. 823 - 500 = 323 cm cubed. To convert to cubic metres, divide by 1000000.
density=mass/volumeweight the stone, this gives you the massplace the stone in a known volume of water, take away the new volume from the old, you now have the volume of the stonePlug the values into the equation - make sure you have matching units, e.g. kg/m3
Weigh the stone 9get the reading in kilograms). Then fill a container right to the brim with water. Put the stone in, and measure the volume of water that spills out - a good way to do this is to have a second container outside the first to catch the spill. The weight of the stone divided by the volume of water spilled is the density, but watch the units you use! You need the mass in kg and the volume of water in cubic meters. 1 millilitre = 1 millionth of a cubic meter, that should help!
Add an answer