The key difference between the mirror formula and the lens formula lies in the sign convention used for the object distance in their respective equations. The reference clarifies the mathematical difference.
Here's a breakdown:
Formulas
| Feature | Mirror Formula | Lens Formula |
|---|---|---|
| Formula | 1/v + 1/u = 1/f | 1/v - 1/u = 1/f |
| u | Object Distance | Object Distance |
| v | Image Distance | Image Distance |
| f | Focal Length | Focal Length |
As shown in the table, the mirror formula uses a plus sign (+) between the reciprocals of the image distance (v) and the object distance (u), while the lens formula uses a minus sign (-). According to the provided resource, the mirror reflects light, while the lens refracts it. This difference in how they manipulate light affects the formula.
Key Differences Explained
- Sign Convention: The primary difference is the "+"" versus "-" sign. This reflects the different ways mirrors and lenses form images.
- Light Manipulation: Mirrors reflect light, while lenses refract light.
- Focal Points: A plane mirror does not have a focal point, whereas lenses have two focal points, F and 2F.
