In: Physics
An object 20 cm tall is placed at 50 cm in front of a converging lens with a focal length of 5 cm.
A. Find the location and nature of the image.
B. Draw the diagram
(A) We have to find the location and nature of the imagr. If u is the object distance, v is the image distance and f is the focal length, then the lens formula is given by,
For a converging lens (convex lens) f is positive and u is negative. So f = 5 cm and u = -50 cm. Substituting the values in the equation of v,
The image is 5.55 cm on the positive side of the mirror. That means it is between f and 2f. Since v is positive it is a real image.
The magnification is given by,
Also given height of the object = 20 cm. If ho is the height of the object and hi is height of the image, then
So the height of the image is 2.2 cm. It is smaller than the object and the negative sign indicate that it an inverted image.
(B) The ray diagramis given below