2. PICTURE IT…
• With this lesson make sure you can visualize what the question is asking. Draw
a picture or search images on the Internet
3. THE TOUGH QUESTION
• The following is the most missed question in M11 L2. The content is the same
but the number is changed.
• A square with an area of 100cm^2 is rotated to form a cylinder. Find the
volume.
• Hint: Visualize it.
4. SEE IF THE PICTURE HELPS
• Here is what the word problem is talking about.
The dotted line is
the line of rotation,
the square is going
to rotate around
its side.
The square creates a
cylinder that has the
radius equal to the
length of one side of the
square and the height of
the cylinder is equal to
one side of the square
5. HOW TO SOLVE IT
• Since the area of the square is 100cm^2, that means each side of the square
is 10
• According to the picture, the radius of the cylinder is 10 and the height of
the cylinder is 10.
• V=Ah (capital A means area of the base)
• V=𝜋𝑟2
ℎ
• V= 𝜋(10^2)(10)
• V=3142cm^3
