Question

An object is placed at a distance of 30 cm from a concave lens to focal length 30 cm.
a). use the lens formula to determine the distance of the image from the lens
b). list 4 characteristics of image in this case (nature, position,size,erect/inverted)
c). draw a labelled diagram to justify your answer of part (b)​

Answer 1

Answer:

Explanation:

Concave lens produce a virtual erect diminished image

By using len's formula, By consention μ=30 & F=−30

μ 1  +  v 1  =  f 1 ⇒  30 1 +  v 1  =−  30 1 ⇒  v 1  =−  30 1  −  30 1 ⇒  v 1 =−  15 1 v 1

​  

=−0.066

So image is erect, virtual, 15cm from the lens (between lens & object).