# Lesson Worksheet: Concave Lenses Physics • 9th Grade

In this worksheet, we will practice defining a concave lens, describing the paths of light rays refracted through it, and explaining how rays are focused by such lenses.

Q1:

Which of the points A, B, C, and D shown in the diagram is closest to the focal point of the concave lens? • APoint D
• BPoint B
• CPoint A
• DPoint C

Q2:

At which of the points A, B, C, and D shown in the diagram is the angle of refraction greatest? • APoint C
• BPoint A
• CPoint B
• DPoint D

Q3:

Which of the following diagrams correctly shows the paths of light rays exiting a concave lens if the light rays enter the lens parallel to the axis of the lens? • A(E)
• B(C)
• C(B)
• D(A)
• E(D)

Q4:

Which of the objects shown is a concave lens? • A(E)
• B(D)
• C(C)
• D(B)
• E(A)

Q5:

Light rays converging to a point are incident on a concave lens, as shown in the diagram. Which of the other diagrams (A), (B), (C), (D), most correctly shows the directions of the rays that exit the lens?  • A(A)
• B(C)
• C(B)
• D(D)

Q6:

Part of a concave lens is shown. No light rays pass through the lens but several possible lines normal to the surface of the lens are shown. Which line on the left-hand side of the lens is normal to the surface at the point that the line contacts the surface?

• ALine D
• BLine C
• CLine B
• DLine A

Which line on the right-hand side of the lens is normal to the surface at the point that the line contacts the surface?

• ALine G
• BLine E
• CLine H
• DLine F

Q7:

Which of the following diagrams correctly shows the paths of light rays passing through a concave lens if the light rays enter the lens parallel to each other but at an angle to the axis of the lens, as shown? • A • B • C • D Q8:

Which of the following statements correctly describes a concave lens?

• AA concave lens decreases in thickness from its center to its edges.
• BA concave lens is thicker than a convex lens.
• CA concave lens increases in thickness from its center to its edges.
• DA concave lens has uniform thickness.

Q9:

Parallel light rays pass through a convex lens and are focused at a point, as shown in the diagram. Which of the following diagrams correctly shows the paths of light rays if they pass first through a concave lens before they pass through the convex lens? The path of light rays through the convex lens is shown as well as the position of the concave lens that will be added. • A • B • C • D Q10:

Parallel light rays fall on the object shown in the diagram. Which of the other diagrams, (a), (b), (c), and (d), correctly shows how the rays move through and out of the object?  • A(d)
• B(c)
• C(b)
• D(a)