Q.

In the figure shown alongside, side length of the square is 2a units.

Assertion (A): Area of smaller circle = Area enclosed between two circles.

Reason (R):Radius of outer circle =2×(Radius of inner circle).

1 Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of Assertion (A).  
2 Both Assertion (A) and Reason (R) are true but Reason (R) is not the correct explanation of Assertion (A).  
3 Assertion (A) is true but Reason (R) is false.    
4 Assertion (A) is false but Reason (R) is true.  

Ans.

(1)

Let R and r be the radii of outer and inner circle respectively. 
Diameter of inner circle = 2a


r=aR=a2+a2=2aArea enclosed between two circles=Area of outer circle-Area of inner circle=πR2-πr2=π(2a)2-πa2=2πa2-πa2=πa2=Area of smaller circle

Both Assertion (A) and Reason (R) are true and Reason (R) is correct explanation of Assertion (A).