What is the measure of central angle of the arc. Whose length is 11 cm and radius of the circle is 14 cm?

Solution (By Examveda Team)

$$\eqalign{ & \theta = \frac{l}{r}{\text{ radian}} = \frac{{11}}{{14}}{\text{ radian}} \cr & \because \pi {\text{ radian}} = {180^ \circ } \cr & \therefore 1{\text{ radian}} = \frac{{{{180}^ \circ }}}{\pi } \cr & \therefore \frac{{11}}{{14}}{\text{ radian}} = \frac{{180}}{{\frac{{22}}{7}}} \times \frac{{11}}{{14}} \cr & = \frac{{180 \times 11 \times 7}}{{22 \times 14}} \cr & = {45^ \circ } \cr} $$