Lesson: Surface Area of Cylinders

2019 Views
3 Favorites

Lesson Objective

We will be able to calculate the surface area of cylinders.

Lesson Plan

Do Now: (5 minutes)

1) Hilda rented a car at a cost of \$30 a day plus \$0.15 per mile. Write an expression that can be used to find the total cost of renting car and driving it m miles?

2) 3 pounds of grapes cost \$4.53. How much do 7 pounds of grapes cost?

3) Find the surface area of this rectangular prism. (8mm x 2mm x 3 mm)

Direct Instruction: (20 minutes)
Yesterday we learned how to find the surface area of rectangular prisms. What did we have to do to find the surface area of a rectangular prism?

Today we are going to find the surface area of a cylinder. How is a cylinder different from a rectangular prism?

To find the surface area of a cylinder, we have to find the area of each circular base plus the area of the curved surface.

Let's look at a net of a cylinder.  What do we notice about the curved cylinder? (it's really just a rectangle).  What is the length of the rectangle equal to? (The circumferece of the circle)  What is the width of the rectanlge equal to? (The height of the cylinder)

What surfaces so we need to find the area of in order to have the areas of all faces of the cylinder?

Surface area of cylinder = 2(πr²) + 2(πr)h

Ex. Draw a cylinder with a radius of 2m and a height of 7m.

Ex. A circular fence that is 2 feet high is to be built around the outside of a carousel. The distance from the center of the carousel to the edge of the fence will be 35 feet. How much fencing material is needed to make the fence around the carousel?

Guided Practice: (10 minutes)
surface area of cylinders guided practice

Assessment: (10 minutes)
surface area of cylinders work-out

Lesson Resources

 surface area of cylinders guided practice   Classwork 1,009 surface area of cylinders work out   Assessment 745