Quiz on Thin Converging Lenses

What is the primary function of a converging (convex) lens?

• To diverge light rays
• To collect light rays at a point
• To reflect light rays
• To absorb light rays

What is the focal length of a lens?

• The distance between the lens and the object
• The distance between the principal focus and the optical center
• The distance between the two principal foci
• The thickness of the lens

Which statement is true about the principal focus of a lens?

• It is located on the optical center
• It is the point where light rays diverge
• It is where parallel rays converge after refraction
• It is the same as the focal length

How many principal foci does a thin converging lens have?

• One
• Two
• Three
• Four

What happens to a ray of light that passes through the optical center of the lens?

• It is refracted towards the principal focus
• It passes straight without deviation
• It diverges
• It is absorbed by the lens

If a ray of light is parallel to the principal axis before entering a convex lens, what will happen to it after refraction?

• It will continue parallel
• It will diverge
• It will pass through the optical center
• It will refract through the principal focus

What is the principal axis of a lens?

• A line that passes through the optical center and is parallel to the lens surface
• A line that passes through the principal focus
• A line that is perpendicular to the lens surface
• A line that connects the two principal foci

In the context of lenses, what does the term 'optical center' refer to?

• The point where light rays converge
• The center of the lens where light passes straight
• The point where the lens is thickest
• The midpoint between the two principal foci

What effect does a thin converging lens have on light rays that are not parallel to the principal axis?

• They are absorbed
• They are reflected
• They are refracted towards the principal focus
• They pass straight through

Which of the following best describes the relationship between the principal focus and the optical center?

• They are the same point
• They are always at equal distances from each other
• The principal focus is always on the same side as the incoming light
• The optical center is always between the two principal foci