Question

today's challenge tell me the perimeter formula of half circle you will get 40 points

Answer 1

perimeter means circumference of circle.

Circumference of circle =pie *d
circumference of half circle=(pie)R+2R


hope it will be right

Answer 2

Perimeter (Circumference) of circle = 2πr

Now a semicircle is half of the circle. So the perimeter will also become the half of it.

Hence the perimeter of half of circle, that is, semicircle = 1/2 × 2πr

= πr cm.

Now The diameter will also contribute to form the perimeter

Hence perimeter = πr + 2r

= r(π + 2)

More information :-

» In a similar way, the area of semicircle = πr²/2

» Perimeter of quadrant (one-fourth) of the circle = πr/2 + 2r

» Area of one fourth of circle = πr²/4

» Area of a sector of circle =
$\frac{ \theta }{360} \times \pi r {}^{2}$
Where, ∅ = Angle made by the sector.

» Perimeter of sector =
$\frac{ \theta }{360} \times 2\pi r + 2r\\ \\ = \frac{ \theta }{180} \times \pi r + 2r$