Question

Find the angle in degree subtended at the centre of a circle by an arc, for the given,

$radiusofcircle=20cm,lengthofarc=78.50cm(\pi =3.14)$

Answer 1

Length of an arc subtending an angle $\theta =\frac{\theta }{360}\times 2\pi R$ where R is the radius of the circle.
So, $78.50=\frac{\theta }{360}\times 2\times \frac{22}{7}\times 20$
Hence, Angle subtended $={225}^0$