Lenses

Front

What is a convex lens?

Back

A convex lens is a lens that is thicker in the middle than at the edges, causing light rays that pass through it to converge.

Front

What is a concave lens?

Back

A concave lens is a lens that is thinner in the middle than at the edges, causing light rays that pass through it to diverge.

Front

What is the principal focus of a lens?

Back

The principal focus is the point where parallel rays of light either converge (in a convex lens) or appear to diverge from (in a concave lens).

Front

What type of image is formed by a convex lens when the object is beyond the focal point?

Back

A real and inverted image is formed when the object is beyond the focal point.

Front

What type of image is formed by a concave lens?

Back

A concave lens always forms a virtual, upright, and reduced image.

Front

What is the difference between real and virtual images?

Back

Real images can be projected on a screen and are inverted, while virtual images cannot be projected and are upright.

Front

What is the formula for the lens maker's equation?

Back

1/f = (n - 1) * (1/R1 - 1/R2), where f is the focal length, n is the refractive index, and R1 and R2 are the radii of curvature.

Front

What is the significance of the focal length in lens optics?

Back

The focal length determines how strongly the lens converges or diverges light rays.

Front

What type of lens is commonly used in eyeglasses for nearsightedness?

Back

Concave lenses are used in eyeglasses for nearsightedness to diverge light rays.

Front

What is a ray diagram?

Back

A ray diagram is a graphical representation used to show the path of light rays through a lens or mirror.