Question

. If a square with each side 'a' is joined from opposite sides to form a cylinder, then area of each circular end (ignoring units) is a^2. (2)a^2/4pie. (3) a^2/pie. (4) a^2/4​

Answer 1

Answer:

2

Step-by-step explanation:

let rad. be r

circumference=2πr

2πr=a

r=a/2π

area=π.a/2πsquare

a^2/4π

Answer 2

Final answer: Area of each circular end of the cylinder =  $\frac{a^{2}}{4\pi}$

Option (2) is correct answer.

Given that: We are given square with each side "a" is joined from opposite sides to form a cylinder.

To find: We have to find the area of each circular end.

Explanation:

• Given that length of each side of a square = a

• When the square of side “a“ is folded to make a cylinder, then the circumference of each circular end of the cylinder will be “a”.

• To  calculate the circumference of each circular end of the cylinder:

Base of a cylinder is circle.

Circumference of each circular end of the cylinder = Circumference of the  circle = $2 \pi r$

Where, r = Radius of the cylinder = Radius of the circle

$a=2\pi r\\\\r=\frac{a}{2\pi}$

• Area of each circular end of the cylinder = Area of circle = $\pi r^{2}$

• Substitute the value of r.

• Area of each circular end of the cylinder  $=\pi *\frac{a}{(2\pi )^{2}}$

                                                                                $= \pi *\frac{a^{2}}{2^{2}\pi ^{2}}\\\\= \pi *\frac{a^{2}}{4\pi^{2}}\\\\=\frac{a^{2}}{4\pi}$

• Hence, area of each circular end of the cylinder =  $\frac{a^{2}}{4\pi}$

Option (2) is correct answer.

• Radius of the cylinder $r=\frac{a}{2\pi }$, then area of each circular end of the cylinder = $\frac{a^{2}}{4\pi}$

By that way option (1) $a^2$ is wrong answer.

• Radius of the cylinder $r=\frac{a}{2\pi }$, then area of each circular end of the cylinder = $\frac{a^{2}}{4\pi}$

By that way option (3) $\frac{a^2}{\pi}$  is wrong answer.

• Radius of the cylinder $r=\frac{a}{2\pi }$, then area of each circular end of the cylinder = $\frac{a^{2}}{4\pi}$

By that way option (4) $\frac{a^2}{4}$ is wrong answer.

To know more about the concept please go through the links

https://brainly.in/question/2126417

https://brainly.in/question/1096040

#SPJ2