1. What is the Lens Formula?

The lens formula is a fundamental equation in optics that relates the focal length of a lens to the object distance and image distance. For convex lenses, it helps determine where an image will form based on the object's position relative to the lens.

2. How Does the Calculator Work?

The calculator uses the lens formula:

Where:

• \( di \) — Image distance (cm)
• \( f \) — Focal length (cm)
• \( do \) — Object distance (cm)

Explanation: The formula calculates the distance between the lens and the image formed, based on the lens's focal length and the object's distance from the lens.

3. Importance of Image Distance Calculation

Details: Calculating image distance is essential for understanding image formation in optical systems, designing cameras, microscopes, telescopes, and other lens-based instruments.

4. Using the Calculator

Tips: Enter focal length and object distance in centimeters. Both values must be positive numbers. The calculator will compute the corresponding image distance.

5. Frequently Asked Questions (FAQ)

Q1: What happens when object distance equals focal length?
A: When do = f, the image distance becomes infinite, meaning the rays emerge parallel and no real image is formed.

Q2: What does a negative image distance indicate?
A: A negative di value indicates a virtual image formed on the same side as the object (common in concave lenses or when using convex lenses with objects inside the focal point).

Q3: How does focal length affect image distance?
A: Longer focal lengths produce images farther from the lens, while shorter focal lengths bring images closer to the lens for the same object distance.

Q4: Can this formula be used for concave lenses?
A: Yes, but with appropriate sign conventions (focal length is negative for concave lenses).

Q5: What are practical applications of this calculation?
A: Used in photography (focusing), ophthalmology (corrective lenses), microscopy, and various optical instrument designs.