Question

An object is placed 2.5 cm away from a converging lens with a focal length of 1.5 cm

Answer 1

The correct answer is "-1.5 cm".

Step-by-step explanation:

The given values are:

Object is placed,

u = 2.5 cm

Focal length,

f = 1.5 cm

On applying the lens formula, we get

⇒
`(1)/(u) +(1)/(v) =(1)/(f)`

or,

⇒
`(1)/(v) =(1)/(u) -(1)/(f)`

On substituting the given values, we get

⇒
`=(1)/(2.5) -(1)/(1.5)`

⇒
`=(1.5-2.5)/(3.75)`

⇒
`=(-1)/(3.75)`

⇒
`v=-3.75 \ cm`

As we know,

Magnification,
`m=(v)/(u)`

On substituting the values, we get

⇒
`=(-3.75)/(2.5)`

⇒
`=-1.5 \ cm`