Question

Doctor suggest a lens of power 0.5D to a person calculate the focal length​

Answer 1

Given

P = +1.5 D

Find out

Find outWe need to find out the focal length of the given lens

Solution

We know that

f = 1/P

Where,

f is the focal length

P is power

Given

P = +1.5 D

Find out

We need to find out the focal length of the given lens

Solution

We know that

f = 1/P

Where,

f is the focal length

P is power

f = 1/P

= 1/+1.5 = 0.67 m.

As the power of the lens is (+ve), the lens is converging.

= 1/+1.5 = 0.67 m.

As the power of the lens is (+ve), the lens is converging.

Answer 2

Answer:

focal length= 1/power of lens

hence, f= 1/0.5D

= 2/1

f= 2m