Mammoth Memory

Convex lens – object at `2F`

This means the object is two principal focal lengths from the convex lens.

A ray diagram can be constructed using the two standard rules

  1. From the object, pass a parallel line through the principal focal point
  2. From the object, pass a ray line through the centre of the convex lens.

 

Ray diagram of an object at 2F away from a convex lens

We can see that when the object is two principal focal lengths from the convex lens, the image can appear on a screen exactly at two principal focal lengths on the other side of the lens. The image will be inverted but can be captured on a screen.

The image of an object at 2F is on the opposite side of the lens, inverted, same size and real

 

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