Question

4. In two concentric circles the chord of bigger circle touches the smaller circle and raddi of
bigger and smaller circles are "R" and r then length of the chord is
A) √R2-r22
B) 2√R2+R2
C)2√r2-R2
2√R2-r2​

Answer 1

Answer:

D) 2√$R^{2}$-$r^{2}$​

Step-by-step explanation:

Applying pythagoras theorem in triangle ABC, we get

AB= √$R^{2}$-$r^{2}$​

length of cord = 2√$R^{2}$-$r^{2}$​

(Radius is perpendicular to the tangent and if a perpendicular is drawn from the center of the circle bisects the cord )