9. What is the curved surface area of a cylinder with diameter of 36cm and height 240mm?
A. 5428,7 cm2 B. 2714,3 cm2 C. 24429 cm2
To find the curved surface area of a cylinder, we can use the formula: CS_area = 2πrh, where r is the radius of the base and h is the height of the cylinder.
Given that the diameter of the cylinder is 36 cm, we can find the radius by dividing it by 2: r = 36 cm / 2 = 18 cm.
Given that the height of the cylinder is 240 mm, we can convert it to cm: h = 240 mm * (1 cm/10 mm) = 24 cm.
Plugging these values into the formula, we get: CS_area = 2π * 18 cm * 24 cm = 2π * 432 cm² ≈ 2714.3 cm².
Therefore, the curved surface area of the cylinder is approximately 2714.3 cm².
The correct answer is B. 2714.3 cm².
To find the curved surface area of a cylinder, we can use the formula:
Curved Surface Area = 2πrh
where r is the radius of the cylinder and h is the height.
Given that the diameter of the cylinder is 36 cm, we can find the radius by dividing the diameter by 2:
Radius (r) = 36 cm / 2 = 18 cm
However, the height is given in millimeters, so we need to convert it to centimeters by dividing by 10:
Height (h) = 240 mm / 10 = 24 cm
Now we can substitute the values into the formula:
Curved Surface Area = 2π(18 cm)(24 cm)
Calculating this, we get:
Curved Surface Area ≈ 2714.3 cm^2
Therefore, the answer is B. 2714,3 cm^2.