Question

A circular wire of radius 7 cm is cut and bent again into an arc of a circle of radius 12 cm. The angle subtended by the arc at the centre is 

A. 50° 

B. 210° 

C. 100° 

D. 60° 

E. 195°

Answer 1

Here, radius of circular wire is r=7 cm 

So, 

length of wire=2×π×r 

=2×π×7 

=14×π 

Wire is cut and bent again into an arc of a circle of radius 12 cm. 

So,length of arc=length of wire=14×π 

We know, angle subtended by the arc is given by,

=210°