Question

В каком случае вогнутая линза будет собирающей?

Answer 1

Если линзы сделаны из материала оптически менее плотного, чем окружающая среда (например, пустотелые линзы в воде), собирающими будут вогнутые, а рассеивающими — выпуклые.

Answer 2

Understanding Convex Lenses

A convex lens can act as a converging lens under certain conditions. Let's explore the circumstances under which a convex lens behaves as a converging lens.

A Convex Lens as a Converging Lens

A convex lens behaves as a converging lens when the object is placed beyond its focal point.

The focal point of a convex lens is the point where parallel rays of light converge after passing through the lens. When an object is placed beyond this focal point, the rays of light converge to form a real image on the opposite side of the lens.

Mathematical Condition for Convergence

The mathematical condition for a convex lens to act as a converging lens is given by the lens formula:

1/f = 1/v - 1/u

Where: - f is the focal length of the lens - v is the image distance - u is the object distance

When the object distance u is greater than the focal length f, the lens formula yields a positive value for the image distance v, indicating that the image is formed on the opposite side of the lens, making the convex lens act as a converging lens.

Conclusion

In conclusion, a convex lens behaves as a converging lens when the object is placed beyond its focal point, satisfying the mathematical condition described by the lens formula. This results in the formation of a real image on the opposite side of the lens.