A cylindrical container closed at both ends, has a radius of 7cm and height 5cm [Take π = 22/7] Find the total surface area of the container
Answer Details
The total surface area of the cylindrical container is the sum of the areas of its top, bottom, and lateral surface.
The top and bottom of the container are both circles, each with an area of πr², where r is the radius of the container. So the total area of the top and bottom is 2πr².
The lateral surface of the container is a rectangle that has been rolled into a cylinder. The length of the rectangle is the circumference of the circle, which is 2πr. The height of the rectangle is the height of the container, which is given as 5cm. So the area of the lateral surface is 2πrh.
Therefore, the total surface area of the container is:
2πr² + 2πrh
Substituting the given values for r and h, we get:
2 × (22/7) × 7² + 2 × (22/7) × 7 × 5
= 2 × (22/7) × 49 + 2 × (22/7) × 35
= (22/7) × 2 × (49 + 35)
= (22/7) × 168
= 528 cm²
Therefore, the total surface area of the container is 528 cm². So, the correct option is (D) 528cm².