Question

A steel bar has a mass of 4,000 kilograms and a volume of 0.5 cubic meters . Calculate its density. Write your answer as a whole number.

Answer 1

The equation for density is:

`D=(m)/(V)`

where the mass is in grams and the volume is in
`cm^(3)`.

We are given 4,000 kilograms, and we know that there are 1,000 grams in 1 kilogram, so we need to multiply to convert to grams:

`4,000*1,000=4,000,000g`

We are also given 0.5
`m^(3)`, and we need to convert to
`cm^(3)`. We know that there are 100 cm in 1 m, and since we are talking about cubic volume, we must also raise 100 to the 3rd power:
`100^(3)=1,000,000cm`. So now we know that there are 1,000,000
`cm^(3)` in 1
`m^(3)`. We need to then multiply 1,000,000 cm by 0.5 in order to find the volume that was given in the question:

`1,000,000*0.5=500,000cm^(3)`

So now that we have the correct units, let's plug them into the equation:

`D=(4,000,000g)/(500,000cm^(3))`

`D=(8g)/(cm^(3))`

So now we know that the density is 8g/cubic centimeter.