Home
Class 10
PHYSICS
Doctor has prescribed a lens having powe...

Doctor has prescribed a lens having power +1.5D. What will be the focal length of the lens? What is the type of the lens and what must be the defect of vision?

Text Solution

Verified by Experts

The correct Answer is:
The prescribed lens is convex lens of focal length +0.67 m and the defect in vision is hypermetropia (farsightedness).
Given: Power (P) =+1.5 D
To find: Focal length (f)
Formula: `P=(1)/(f(m))`
Calculation: From formula,
`f=(1.5)=+0.67 m`
The prescribed lens is convex lens as the focal length is positive. Convex lens has positive focal length and it is used for the correction of farsightedness or hypermetropia. Thus, the defect in vision is hypermetropia (farsightedness).
Promotional Banner

Similar Questions

Explore conceptually related problems

Vijay is 16 yr old and wears a spectacle having a power of -2 D .Answer the following question: What Will Be the Focal Length of the Lens? What is the Type of the Lens and What Must Be the Defect of Vision?

Selwyn is 16 yr old and wears a spectacle having a power of +2 D .Answer the following question? What Will Be the Focal Length of the Lens? What is the Type of the Lens and What Must Be the Defect of Vision?

The focal length of a convex lens is 20 cm.What is the power?

If for a lens , f= -20 cm, what is the power of the lens ?

Answer the following questions : What is the power of a lens ?

Answer the following questions : What is the nature of the eye lens and what does the eye lens do?

What is the accommodation power of the lens?

What is the power of lens?