Question

Assertion: Power of a concave lens is negative.
Reason: Focal length ofconcave lens is taken on right hand side ​

Answer 1

$\pink{Assertion\: is \:true \:but\: Reason \:is \:false.}$

• Power of concave lens is negative.

• Power of concave lens is negative.According to sign conventional rule,Focal length of concave/convex lens is taken on left hand side.

Answer 2

From the given question the correct answer is:

Assertion is corrrect but reason is not correct explanation of Reason.

Explanation of  Assertion  : The power of the lens is the reciprocal of the focal length. A concave lens is a diverging lens, so it will always have a negative focal length. Therefore, the power of a concave lens is also negative.

Explanation of Reason:

Power of concave lens is negative.According to sign conventional rule,Focal length of concave/convex lens is taken on left hand side.