How many cubic centimetres of iron is required to construct an open box whose external dimensions are , and provided the thickness of the iron is . If one cubic cm of iron weighs , find the weight of the box.
Step Find the required volume of iron.
Give that, and
Find the external volume of the box:
{Since, the box is open from the top.}
Therefore, the external volume of the box is .
Internal dimensions of the box:
Similarly,
And,
{Since, the box is open from the top.}
Now, find the internal volume of the box:
Therefore, the internal volume of the box is .
Find the volume of the iron used to construct the given box as follows:
Therefore, of iron is required to construct given box.
Step Compute the weight of the box.
Since, it is given that of iron weighs .
Therefore, the weight of the box is given by:
Therefore, the weight of the box is or .