Tanrnayee from Std. X uses spectacles. The power of the lenses in her spectacles is-2.5 D. Answer the following questions:
State the type of lenses used in her spectacles.

Answer the following questions : Aniket from Std. X uses spectacles . The power of the lenses in his spectacles is -0.5 D. Answer the following question : State the type of lenses used in his spectacles.

Tanrnayee from Std. X uses spectacles. The power of the lenses in her spectacles is-2.5 D. Answer the following questions: Find the focal length of the lenses used in her spectacles.

Answer the following questions : State the uses of ethanol.

Answer the following questions : State the use of a telescope .

Answer the following questions: State the use of a periscope.

Surabhi from std. X uses spectacles. The power of the lenses in her spectacles is 0.5 D. Answer the following questions from the given information: Identify the type of lenses used in her spectacles.

Answer the following questions : Aniket from Std. X uses spectacles . The power of the lenses in his spectacles is -0.5 D. Answer the following question : Name the defect of vision Aniket is suffering from .

Answer the following questions : When are bifocal lenses used in spectacles ?