Understanding the Surface Area of a Cone

The video tutorial explains how to calculate the surface area of a cone. It begins with an introduction to the concept, followed by a detailed explanation of how to find the area of the base using the formula πr². The tutorial then covers the formula for the lateral area of a cone, πrl, and demonstrates how to substitute given values into the formula. Finally, the video concludes with the final calculation of the surface area and a reminder to include units in the answer.

What is the first step in finding the surface area of a cone?

• Measure the diameter of the base

• Determine the height of the cone

• Find the area of the base

• Calculate the volume of the cone

Which formula is used to calculate the area of the base of a cone?

• πrl

• 2πrh

• πr²

• 2πr

What does the 'l' represent in the lateral area formula for a cone?

• The height of the cone

• The diameter of the base

• The slant height

• The radius of the base

How do you calculate the lateral area of a cone?

• Using the formula πr²

• Using the formula πrl

• Using the formula 2πrh

• Using the formula 2πr

If the radius of a cone is 4 cm and the slant height is 10 cm, what is the lateral area?

• 40π cm²

• 16π cm²

• 80π cm²

• 20π cm²

What is the total surface area of a cone with a base radius of 4 cm and a slant height of 10 cm?

• 16π cm²

• 56π cm²

• 175.9 cm²

• 179 cm²

Why is it important to include units when calculating area?

• To ensure the calculation is correct

• To indicate the measurement is in volume

• To specify the type of shape

• To show the measurement is squared