8.5 Surface Area of Cones

What is the surface area of a cone with a radius of 2 m and a slant height of 3 m?

• 20 m²

• 25 m²

• 31.42 m²

• 35 m²

What is the surface area of a cone with a radius of 1.5 m and a slant height of 2.5 m?

• 12π m² (≈ 37.70 m²)

• 6π m² (≈ 18.85 m²)

• 8π m² (≈ 25.13 m²)

• 10π m² (≈ 31.42 m²)

What is the surface area of a cone with a radius of 4 inches and a height of 3 inches?

• 36π in² (approximately 113.10 in²)

• 24π in² (approximately 75.40 in²)

• 20π in² (approximately 62.83 in²)

• 32π in² (approximately 100.53 in²)

What is the difference between the lateral surface area and the total surface area of a cone?

• Lateral surface area is the area of the cone's side, while total surface area includes the base area.

• Lateral surface area includes the base area, while total surface area is only the area of the cone's side.

• Lateral surface area is always larger than total surface area.

• Lateral surface area and total surface area are the same.

What is the unit of measurement for surface area?

• Cubic units, such as cubic inches (in³)

• Square units, such as square inches (in²), square centimeters (cm²), or square meters (m²)

• Linear units, such as inches (in) or centimeters (cm)

• Percentage units, such as percent (%)

What does 'slant height' refer to in a cone?

• The distance from the base of the cone to the apex along the side of the cone.

• The height of the cone measured vertically from the base to the apex.

• The radius of the base of the cone.

• The circumference of the base of the cone.

If a cone has a radius of 3 inches and a slant height of 4 inches, what is its surface area?

• 21π ≈ 65.97 in²

• 15π ≈ 47.12 in²

• 18π ≈ 56.55 in²

• 24π ≈ 75.40 in²

How do you find the radius of a cone if you know the surface area and slant height?

• r = (Surface Area / (π(l + r)))

• r = (Surface Area / (2πl))

• r = (Surface Area / (πl))

• r = (Surface Area / (πr))

What is the formula for the surface area of a cone?

• Surface Area = πr²

• Surface Area = πr(r + h)

• Surface Area = πr(r + l)

• Surface Area = 2πr² + 2πrh

If the radius of a cone doubles, how does the surface area change?

• The surface area remains the same.

• The surface area increases by a factor of 2.

• The surface area increases by a factor of 3.

• The surface area increases by a factor of 4, since surface area is proportional to the square of the radius.