Question

When an object is located very far away from a convex mirror, the image of the object is 20.0 cm behind the mirror. Using a ray diagram drawn to scale, determine where the image is located when the object is placed 6.7 cm in front of the mirror. Note that the mirror must be drawn to scale also. In your drawing, assume that the height of the object is 3.0 cm.

first I got 2.25 and 4.01. both answers are wrong please give me a solution

Answer 1

Here I am just solving the problem without ray diagram.

The focal length F is given as [- 20] cm.
U = 6.7 cm: V=?
-1/F = 1/U + 1/V
-0.05 = 0.149 + 1/V
V = - 5.025 cm.
Image is behind the mirror.