Question

An object has a height of 0.066 m and is held 0.210 m in front of a converging lens with a focal length of 0.140 m. (Include the sign of the value in your answers.)

(a) What is the magnification?
(b) What is the image height?
m

Answer 1

Step-by-step explanation:

Given that,

Size of object, h = 0.066 m

Object distance from the lens, u = 0.210 m (negative)

Focal length of the converging lens, f = 0.14 m

If v is the image distance from the lens, we can find it using lens formula as follows :

`(1)/(v)-(1)/(u)=(1)/(f)\\\\(1)/(v)=(1)/(f)+(1)/(u)\\\\(1)/(v)=(1)/(0.14 )+(1)/((-0.21))\\\\v=0.42\ m`

(a) Magnification,

`m=(v)/(u)\\\\m=(0.42)/((-0.21))\\\\m=-2`

(b) Magnification,
`m=(h')/(h)`

h' is image height

`-2=(h')/(0.066)\\\\h'=-2* 0.066\\\\h'=-0.132\ m`

Hence, this is the required solution.