Question

A 13.2 cm tall object is placed in front of a convex lens. As a

result, an image is with a height of -46 cm is produced on a screen
placed 80.5 cm from the lens. Find the focal length of the lens.

Answer 1

To find the focal length of the convex lens, use the lens formula: 1/f = 1/v - 1/u, where f is the focal length, v is the image distance, and u is the object distance. Solving the equation with the given values, the focal length of the convex lens is -1.24 cm.

Step-by-step explanation:

To find the focal length of the convex lens, we can use the lens formula:

1/f = 1/v - 1/u

Where f is the focal length, v is the image distance, and u is the object distance.

From the question, we know that the object distance (u) is 13.2 cm, the image distance (v) is -80.5 cm (negative sign indicates a virtual image), and the height of the image (v) is -46 cm (negative sign indicates an inverted image).

Using these values, we can solve the equation to find the focal length:

1/f = 1/(-80.5) - 1/13.2

f = 1/(-0.805) - 1/0.132 = -1.24 cm

Therefore, the focal length of the convex lens is -1.24 cm.