Distance between optic centre and image

When a screen is held in front of a convex lens and adjusted to get a sharp and bright image of a distant object, the distance between the optic centre of the lens and the image can be determined. This distance is known as the object distance (u) and can be calculated using the lens formula:

1/f = 1/v - 1/u

Where:
- f is the focal length of the lens
- v is the image distance (distance between the lens and the image)
- u is the object distance (distance between the lens and the object)

Process of getting a sharp and bright image

To obtain a sharp and bright image using a convex lens, the following steps can be followed:

1. Place the convex lens on a stand or hold it firmly.
2. Keep a screen (such as a white sheet of paper) at a reasonable distance from the lens. This screen will act as the image surface.
3. Look through the lens and adjust the screen position until a sharp and bright image of a distant object is formed on the screen.
4. Measure the distance between the optic centre of the lens and the screen (image distance, v).

Calculating the object distance

Once the image distance (v) is determined, the object distance (u) can be calculated using the lens formula mentioned earlier:

1/f = 1/v - 1/u

Since the distant object is considered to be at infinity, the term 1/u can be approximated to zero. Therefore, the equation simplifies to:

1/f = 1/v

Solving this equation, we can find the value of u:

u = fv / (f - v)

Significance of the distance between optic centre and image

The distance between the optic centre of the lens and the image is important as it helps determine the magnification and size of the image formed by the lens. By measuring this distance accurately, one can understand the characteristics of the lens and its ability to form images. Additionally, this distance is essential in various applications of convex lenses, such as in cameras, telescopes, and microscopes, where the distance between the lens and the image affects the quality and clarity of the final image.

Real and inverted image