Question

5.
We are given a concave lens of focal length 15 cm. Draw a ray diagram to show
the nature, size and position of the image formed when the object is kept at a
distance of
(a) 30 cm (b) 15 cm (c) 10 cm
from the lens.
(Note: For drawing ray diagrams, use an appropriate scale.)​

Answer 1

Answer:

when we have a concave lens of focal length 15 cm . we can draw the nature , size and position of the image formed when the the object is kept at a distance of 30 cm , 15 cm and 10 cm respectively from the lens the diagram in the the above shows the same and it's appropriate for that condition . I mention all parts in only one diagram , you can make separate diagrams for that .

Answer 2

Solution how

focal length= 15cm

Distance of image= 10cm

1/u = -(1/10) – (1/- 15)

1/u =1/15 – 1/10

1/u = -0.033

u = -30 cm

So, the object is placed 30 cm away from the concave lens