Aim: How do we calculate the surface area of cylinders?
The surface(base) of a cylinder is a circle?
It's area is (pie)r(radius)^2
Example: (pie)6(radius)^2=36(pie)
http://jwilson.coe.uga.edu/emt669/Student.Folders/Pearman.lori/essay1/Essay11.gif
The surface area formula of a cylinder is : L.A(lateral area)+2B(base area (pie)r^2)
http://www.fea-optimization.com/ETBX/solidprop_help_files/surfarea.gif
The lateral area formula of a cylinder is: L.A (pie)d(diameter)h or 2(pie)rh
Example Questions:
1. A cylinder has the height of 15ft and radius of 6 ft? What is the lateral area?
L.A=(pie)dh
(pie)12*15
= answer: (pie)180ft^2 or 565.2ft^2
*reminder: don't forget to add the units*
2. A cylinder has the Lateral Area of 300in, an base area of 78.5in, a height of 12in and radius of 4? What is the surface area?
S.A.=L.A. +2B
=300+2(78.5)
=300+157
=457in^2
TRY IT YOURSELF!
A cylinder has the height of 14cm and the radius of 5cm? What is the surface area and lateral area of the cylinder?
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