Question

A roller has a diameter 0.5m and length 1.5m . find the no.f revelutions it has to make to cover an area of 264sq.m​

Answer 1

GivEn:

• A roller has a diameter is 0.5m
• Length of the diameter is 1.5m

To find:

• The no of revolutions it has to make to cover an area of 264 sq.m?

Solution:

☯ Let Radius of the roller be r m.

★ According to the Question:

Curved surface area of roller = Area covered by the roller in one revolution.

Now, Finding radius of the roller,

➯ R = d/2

➯ 0.5/2

➯ 0.25

Thus, Radius of the roller is 0.25

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Now, Finding curved surface area of the roller,

We know that,

★ Curve surface area = 2πrh

Here,

• r = 0.25m
• Height = 1.5m

Therefore,

➯ 2 × 22/7 × 0.25 × 1.5

➯ 44/7 × 0.375

➯ 33/14 sq m.

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Now, Finding number of revolutions covered in an area of 264sq.m,

➯ Area ÷ area covered by the roller in one revolution.

➯ 264/33/14

➯ 14 × 8

➯ 112.

∴ Hence, Number of revolutions covered in an area of 264m² is 112.

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★ Some formulas related to it :

• Volume of cylinder = πr²h
• Surface area = 2πrh + 2πr²
• Lateral area = 2πrh
• Base area = πr²
• Height = V/πr²
• Radius = √v/πh