Topic 5 - Light And The Electromagnetic Spectrum - Lenses

Question 1

What is the definition of Focal Length?

Answer 1

The distance between the lens and the focal point

Focal length determines how strongly the lens converges or diverges light.

Question 2

What is a Focal Point?

Answer 2

The point where all horizontal rays meet after passing through the lens

The focal point is crucial for understanding how lenses form images.

Question 3

What is the relationship between the Power of the lens and its Focal Length?

Answer 3

Power of the lens is the inverse of the focal length

Power is measured in diopters (D).

Question 4

True or False: A shorter focal length results in greater power of a lens.

Answer 4

True

This is because a shorter focal length indicates a stronger convergence of light rays.

Question 5

How does the thickness of a lens affect its focal length?

Answer 5

A thicker lens means shorter focal length, so greater power

Lens thickness is a key factor in optical design.