Savitri had to make a model of a cylindrical kaleidoscope for her science project. She wanted to use chart paper to make the curved surface of the kaleidoscope. (see Fig 13.10). What would be the area of chart paper required by her, if she wanted

Explanation

Required area can be given as the curved surface area of the cyllinder.

We know, curved surface area of a cyllinder, `A = 2pirh`

Here, `h = 25cm and r = 3.5cm`

So, `A = 2**22/7**3.5**25 = 22**25 = 550cm^2`

So, required area will be `550cm^2.`