Question

The power of a lens is +2 D. Which of the following statements is correct?



A .Focal length of the lens is +50 cm.

B . The lens is converging in nature.

C. The lens is diverging in nature

D. Both A and B​

Answer 1

Explanation:

the answer is d as per my opinion

Answer 2

Given,

Power of the lens = +2D

To find,

Determination of focal length and the nature of the lens, in order to choose the correct statements.

Solution,

Here, we have to use the following mathematical relationship between, power and focal length of a lens. Which is -

Power = 1/focal length

Now, by putting the given values, we get,

2 = 1/focal length

2× focal length = 1

focal length = ½ metres

focal length = +50 cm

So, value of the focal length is +50 cm.

Which means statement in option A, is absolutely correct.

Now, lenses which are converging in nature, always have positive focal length, as well as positive power. As, the discussed lens also has positive focal length and power, so it will be obviously a converging lens.

Which means statement in option B, is also correct.

Hence, both A and B (ie. focal length = +50 cm , and its a converging lens) are correct statements. (option D)