A right circular cylindrical tunnel of diameter 2 m and length 40 m is

1.	A right circular cylindrical tunnel of diameter 2 m and length 40 m is to be constructed from a sheet of iron. The area of the iron sheet required in m2, isA. 40πB. 80πC. 160πD. 200π
Answer» Correct option is B. 80π Given, Diameter of cylindrical tunnel = 2 m So radius = \(\cfrac22\) = 1 m Length of tunnel = 40 m Area of iron sheet required = 2πrh = 2π × 1 × 40 = 80π m²

A right circular cylindrical tunnel of diameter 2 m and length 40 m is to be constructed from a sheet of iron. The area of the iron sheet required in m2, isA. 40πB. 80πC. 160πD. 200π

Answer»

Correct option is B. 80π

Given,

Diameter of cylindrical tunnel = 2 m

So radius = \(\cfrac22\) = 1 m

Length of tunnel = 40 m

Area of iron sheet required = 2πrh

= 2π × 1 × 40 = 80π m²