Page 37 - RME-Based Bilingual E-Module

LEARNING ACTIVITIES 2

Activities 2.3 Surface Area of Cone

Let’s Observe!

Picture 7. Cone and Net

Let’s Do It!

Prepare your pen and book/paper. We'll find the formula for the surface

area of a cone. Based on the previous activity, we already know that
cone is built on a base (circle) and a curved surface (sector of circle).
Please answer the questions below!

1. Base cone area = area of circle with r radius, find the formula base
cone area!
2. Arc B1B2 = circumference of base = circumference of circle with r
radius, find the formula!

3. Find the formula for the circumference of circle with s radius!
4. Find the formula for area of circle with s radius!
5. Curved surface of cone is sector of circle with s radius, find the formula

for curved surface area. Hint: Look this comparison:

Sector Area TB1B2 Arc B1B2
=
Circle Area with s radius Circum. of Circle with s radius

Let’s Conlude!

Find the formula for Surface Area of Cone!

Upload a photo of your work through the following link:
https://forms.gle/PYA8RmvrJFP8FuJn7

RME-BASED BILINGUAL E-MODULE— 12