Answer with explanation:
Take a thread of length x cm.Convert it into circle of radius r cm.
If you divide the Length of circle by value equal to 2 π, you will obtain radius of the circle.The value 2π is a constant Quantity is an Irrational number.
[tex]\rightarrow \frac{\text{Length of thread}}{2 \pi}=r\\\\ \rightarrow \frac{x}{2 \pi}=r\\\\ \rightarrow x=2 \pi r[/tex]
Diameter of Circle =8 cm
Circumference of a circle with a diameter of 8 cm has radius equal to 4 cm because radius is half of diameter
=2 × 3.14 × 4 cm
= 25.12 cm
⇒So, Actual Length of thread =25.12 cm
Irrational Quantity=2 π=2×3.14=6.28 cm
So Radius
[tex]=\frac{25.12}{6.28}\\\\=4 cm[/tex]
Diameter =Radius × 2
=4 cm × 2
= 8 cm
