An object is placed in front of a convex lens of a focal length 10 cm . What is the nature of the image formed if the object distance is 15 cm ?
Given
Object distance , mu= -15 cm
Focal length, f=10 cm
To find : Nature of the image = ?

Explanation

`1/f =1/u -1/v `
`1/v = 1/f + 1/u`
`=1/(10) + (1)/(-15)`
`1/v =(3-2)/(30) =(1)/(30)`
`1/v =(1)/(30)`
`therefore v=30 cm ` [Image distance]
Magnification , `m=v/u =(30)/(-15) =-2`
`therefore ` Image is real, inverted , 30 cm from lens on the opposite side of the object & magnified 2 times.