Question

If four times the sum of the areas of two circular faces of a cylinder of height 8 cm is equal
to twice the curve surface area, then diameter of the cylinder is

Answer 1

Answer:

Diameter of the cylinder = 8cm

Step-by-step explanation:

Area of the circle = πr²

Curved surface area of a cylinder = 2πrh

Here r = radius and h = height of the cylinder

According to question,

4(πr²+πr²) = 2(2πrh)

4 × 2πr² = 4πrh

2r² / r = h

2r = h

2r = 8  (Height(h) = 8cm is given)

Diameter = 2r

∴ Diameter = 8 cm