AP Physics 2 Quiz: Images Formed By Lenses

What this quiz covers

This quiz focuses on Images Formed By Lenses, giving you a quick way to practice the rules, question types, and explanations that matter most for AP Physics 2.

How to use this quiz

Try each quiz question before looking at the correct answer. Use the explanations to review missed ideas, then come back to similar questions until the pattern feels familiar.

Question 1

1. Real, inverted, and larger than the object
2. Virtual, upright, and smaller than the object (correct answer)
3. Real, upright, and on the far side of the lens
4. Virtual, inverted, and located on the lens surface

Explanation: This question tests understanding of images formed by lenses. Diverging lenses always produce virtual, upright, and reduced images for real objects, regardless of object distance. With the object at 60 cm from a diverging lens of focal length magnitude 20 cm, the parallel ray refracts as if coming from the near focal point while the center ray passes straight through. These refracted rays diverge, so only their backward extensions intersect on the object's side of the lens, confirming a virtual image. The image is upright (as all virtual images are) and smaller than the object because diverging lenses always demagnify. Choice A incorrectly suggests a diverging lens can produce a real, inverted image, revealing a fundamental misconception—diverging lenses cannot converge light from real objects to form real images. When encountering a diverging lens problem, immediately recognize that the image will be virtual, upright, and smaller, then use ray tracing to find its exact position.

Question 2

1. Real, inverted, and larger than the object
2. Real, upright, and on the far side of the lens
3. Virtual, upright, and smaller than the object (correct answer)
4. Virtual, inverted, and formed on the lens surface

Explanation: This question tests understanding of images formed by lenses. A diverging lens always produces virtual, upright, and diminished images for any real object position. When the object is close to the lens, the center ray still passes straight through while the parallel ray refracts as if originating from the near focal point. These rays diverge on the right side, so only their backward extensions can meet, forming a virtual image on the object's side. The image remains upright (as all virtual images are) and appears smaller than the object because the backward extensions meet closer to the lens than the object position. Choice A incorrectly suggests a diverging lens can create a real, inverted, magnified image, showing a fundamental misunderstanding—diverging lenses never form real images from real objects. For any diverging lens problem, immediately conclude the image will be virtual, upright, and reduced, then use ray tracing only to find the precise location.

Question 3

1. Virtual, inverted, and the same size as the object, formed on the lens surface
2. Real, inverted, and the same size as the object, formed on the opposite side of the lens (correct answer)
3. Virtual, upright, and larger than the object, formed on the same side as the object
4. Real, upright, and smaller than the object, formed on the opposite side of the lens

Explanation: This question tests understanding of images formed by lenses. When an object is placed at exactly 2f from a converging lens, rays from each object point converge at exactly 2f on the opposite side, creating a real image. This special position produces an image that is inverted (as all real images are) and exactly the same size as the object—neither magnified nor diminished. This 1:1 imaging is used in copy machines and some optical instruments. Choice A incorrectly suggests the image is larger and virtual, but objects at 2f always produce real, same-size images. To remember this special case, note that 2f is the symmetry point where object and image distances are equal, producing equal sizes.

Question 4

1. Real, upright, and located behind the lens
2. Virtual, upright, and smaller than the object (correct answer)
3. Real, inverted, and located beyond $|f|$
4. Formed on the lens surface and always inverted

Explanation: This problem tests understanding of images formed by lenses. A diverging lens with f = -12 cm always produces virtual images because it spreads rays apart. When an object is placed at 6 cm (any distance), the diverging rays never converge but appear to originate from a point on the same side as the object when traced backward. This virtual image is always upright and smaller than the object, regardless of object distance. Choice C incorrectly suggests diverging lenses can produce real, upright images, which violates the fundamental property that real images are always inverted. For diverging lenses, remember the universal rule: always virtual, upright, and reduced images on the object side.

Question 5

1. Formed on the lens surface and always inverted
2. Real, upright, and located between lens and $f$
3. Real, inverted, and larger than the object (correct answer)
4. Virtual, upright, and smaller than the object

Explanation: This problem tests understanding of images formed by lenses. For a converging lens with f = +8 cm, when an object is placed at 12 cm (between f and 2f = 16 cm), the lens converges rays to form a real image. The ray parallel to the axis passes through the focal point, and the ray through the center continues straight, intersecting beyond 2f on the opposite side. Since the object is between f and 2f, the image forms beyond 2f, making it real, inverted, and larger than the object. Choice A incorrectly assumes converging lenses always produce virtual images when the object is close, missing that only objects inside f produce virtual images. When an object is between f and 2f for a converging lens, always expect a real, inverted, magnified image beyond 2f.

Question 6

1. Virtual, inverted, and formed on the lens surface
2. Real, inverted, and larger than the object
3. Real, upright, and always at $2f$
4. Virtual, upright, and smaller than the object (correct answer)

Explanation: This question tests understanding of images formed by lenses. For a diverging lens with f = -15 cm, rays always diverge regardless of object position. The parallel ray refracts as if coming from the left focal point (diverging), and the center ray continues straight through the lens. These diverging rays never actually meet on the right side, but their backward extensions intersect on the left side to form a virtual image. Diverging lenses always produce virtual, upright, and smaller images located between the object and the lens. Choice A incorrectly suggests diverging lenses can form real images, revealing the misconception that all lenses can produce both real and virtual images. Remember that diverging lenses only form virtual, upright, reduced images for all object positions.

Question 7

1. Real, inverted, and located at $2f$ on the right
2. Virtual, upright, and located at $f$ on the left
3. No finite image forms; rays emerge parallel to the axis (correct answer)
4. A real image forms on the lens surface

Explanation: This question tests understanding of images formed by lenses. When an object is placed exactly at the focal point (20 cm = f) of a converging lens, a special case occurs. The parallel ray refracts through the right focal point as usual, but the focal ray, which starts from the focal point, emerges parallel to the axis after refraction. Since both refracted rays are parallel, they never intersect, meaning no finite image forms. The rays emerge parallel, carrying the image information to infinity. Choice A incorrectly assumes an image forms at 2f, misunderstanding this special case. When an object is at the focal point of a converging lens, refracted rays emerge parallel with no finite image.

Question 8

1. Real, inverted, and larger than the object
2. Virtual, inverted, and smaller than the object
3. Real, upright, and formed on the lens surface
4. Virtual, upright, and larger than the object (correct answer)

Explanation: This question tests understanding of images formed by lenses. For a converging lens with f = +10 cm and an object at 6 cm (less than f), the lens acts as a magnifier. The parallel ray refracts toward the right focal point, but since the object is inside the focal length, this refracted ray diverges from the axis. The center ray passes straight through, and when both rays are extended backward on the left side, they intersect to form a virtual image. This virtual image is upright, larger than the object, and located on the same side as the object. Choice D incorrectly claims virtual images can be inverted, showing misunderstanding that virtual images from single lenses are always upright. When the object is inside the focal length of a converging lens, always expect a magnified virtual image on the object's side.

Question 9

1. Virtual, upright, and smaller than the object
2. Real, upright, and formed at the focal point
3. Virtual, inverted, and always behind the lens
4. Real, inverted, and larger than the object (correct answer)

Explanation: This question tests understanding of images formed by lenses. For a converging lens with f = +8.0 cm and an object between f and 2f (e.g., at 12 cm), rays converge on the opposite side. The parallel ray refracts through the right focal point, the focal ray emerges parallel, and the center ray continues straight. These rays intersect beyond 2f on the right side, forming a real image that is inverted and larger than the object. Choice C incorrectly claims real images can be upright, showing confusion about image orientation in single-lens systems. When an object is between f and 2f for a converging lens, the image is always real, inverted, and magnified beyond 2f.

Question 10

1. Virtual, upright, and larger than the object
2. Real, inverted, and located near the right focal point (correct answer)
3. Real, upright, and located on the lens surface
4. Virtual, inverted, and located at the left focal point

Explanation: This question tests understanding of images formed by lenses. When an object is placed very far from a converging lens (much farther than 2f), incoming rays are nearly parallel. The parallel ray refracts through the right focal point, and the focal ray emerges parallel to the axis after refraction. These rays converge very close to the focal point on the right side, forming a real, inverted image. For distant objects, the image approaches the focal point and becomes very small. Choice A incorrectly suggests the image would be virtual and upright, misunderstanding that converging lenses form real images for objects beyond the focal length. For objects at infinity, converging lenses form real images at the focal point.

Question 11

1. Virtual, upright, and larger than the object
2. Real, upright, and formed on the lens surface
3. Virtual, inverted, and always at the focal point
4. Real, inverted, and smaller than the object (correct answer)

Explanation: This question tests understanding of images formed by lenses. For a converging lens with f = +12 cm and an object at 30 cm (beyond 2f), rays converge on the opposite side to form a real image. The parallel ray refracts through the right focal point, and the center ray continues straight, intersecting beyond the focal point but before 2f. Since the object is beyond 2f, the image forms between f and 2f on the right side, making it real, inverted, and smaller than the object. Choice C incorrectly suggests real images can be upright, revealing confusion about the orientation of real images formed by single lenses. To solve lens problems systematically, identify the lens type, compare object distance to focal points, and trace at least two principal rays to find where they intersect.

Question 12

1. Real, inverted, and located at $2f$
2. Virtual, upright, and located at $f$
3. No finite image forms; rays emerge parallel (correct answer)
4. Formed on the lens surface and always inverted

Explanation: This problem tests understanding of images formed by lenses. When an object is placed exactly at the focal point (15 cm = f) of a converging lens, rays from each object point emerge parallel after refraction. The ray initially parallel to the axis passes through the focal point, while the ray through the focal point emerges parallel, resulting in parallel output rays that never converge. Since parallel rays don't intersect at any finite distance, no image forms at a definite location. Choice A incorrectly assumes an image always forms at a specific location, not recognizing the special case when the object is at f. When an object is placed at the focal point of a converging lens, remember that refracted rays emerge parallel, forming no finite image.

Question 13

1. Real, inverted, and located between lens and $|f|$
2. Virtual, upright, and smaller than the object (correct answer)
3. Real, upright, and located behind the lens
4. Formed on the lens surface and always inverted

Explanation: This problem tests understanding of images formed by lenses. A diverging lens with f = -30 cm always produces virtual images by spreading rays apart. When an object is placed at 90 cm, the diverging rays appear to originate from a point closer to the lens on the same side as the object. This virtual image is upright and smaller than the object, as is always the case for diverging lenses regardless of object position. Choice A incorrectly suggests a real image between the lens and focal point, which is impossible since diverging lenses never converge rays to form real images. For any diverging lens scenario, consistently apply: virtual, upright, reduced image on the object side.

Question 14

1. Virtual, upright, and larger than the object
2. Real, inverted, and smaller than the object (correct answer)
3. Real, upright, and located on the object side
4. Formed on the lens surface and always inverted

Explanation: This problem tests understanding of images formed by lenses. For a converging lens with f = +25 cm, when an object is placed at 60 cm (beyond 2f = 50 cm), rays converge after passing through the lens to form a real image. The principal ray analysis shows that when the object is beyond 2f, the image forms between f and 2f on the opposite side of the lens. This configuration produces a real, inverted image that is smaller than the object, typical of camera or eye lens operation. Choice A incorrectly reverses the image characteristics, suggesting virtual and upright when the image is actually real and inverted. For objects beyond 2f with converging lenses, use the rule: real, inverted, reduced image between f and 2f.

Question 15

1. Virtual, upright, and smaller than the object (correct answer)
2. Virtual, inverted, and formed on the lens surface
3. Real, inverted, and larger than the object
4. Real, upright, and formed at the right focal point

Explanation: This question tests understanding of images formed by lenses. For a diverging lens with f = -10 cm and an object at 10 cm, rays diverge after passing through the lens. The parallel ray refracts as if coming from the left focal point, diverging from the axis, while the center ray continues straight. The backward extensions of these diverging rays intersect on the left side, forming a virtual image between the object and lens. Diverging lenses always produce virtual, upright, and smaller images for any object position. Choice B incorrectly suggests a diverging lens can form real images, revealing the misconception that lens type doesn't constrain image properties. Diverging lenses only form virtual, upright, reduced images regardless of object placement.

Question 16

1. Real, inverted, and smaller than the object (correct answer)
2. Virtual, upright, and larger than the object
3. Real, upright, and located at the left focal point
4. Virtual, inverted, and formed on the lens surface

Explanation: This question tests understanding of images formed by lenses. For a converging lens with f = +5.0 cm and an object at 15 cm (which equals 3f), the object is well beyond 2f. The parallel ray refracts through the right focal point, and the center ray continues straight, intersecting on the right side between f and 2f. Since the object is beyond 2f, the image is real, inverted, and smaller than the object. Choice B incorrectly suggests a virtual, upright image, misunderstanding that objects beyond the focal length of converging lenses always produce real, inverted images. For converging lenses, objects beyond 2f always form real, inverted, reduced images between f and 2f.

Question 17

1. Real, inverted, and located to the right of the lens
2. Virtual, upright, and located to the left of the lens (correct answer)
3. Real, upright, and located on the lens surface
4. Virtual, inverted, and always at the focal point

Explanation: This question tests understanding of images formed by lenses. When a converging lens is used as a magnifier with the object slightly inside the focal length, the refracted rays diverge on the right side. The parallel ray heads toward the right focal point but diverges before reaching it, while the center ray passes straight through. These diverging rays, when extended backward, intersect on the left side to form a virtual image. This virtual image is upright, larger than the object, and located on the same side as the object. Choice A incorrectly identifies the image as real, missing that diverging refracted rays indicate a virtual image. When refracted rays diverge from a converging lens, trace them backward to find the virtual image location.

Question 18

1. Real, inverted, and formed on the lens surface
2. Virtual, upright, and formed at the focal point
3. No finite image forms; rays exit parallel (image at infinity) (correct answer)
4. Real, upright, and larger than the object

Explanation: This question tests understanding of images formed by lenses. When an object is placed exactly at the focal point of a converging lens, a unique situation occurs where no finite image forms. The parallel ray from the object refracts through the far focal point, but since the object is at the near focal point, rays entering the lens are already converging toward that point, so they exit parallel to each other. With all refracted rays parallel, they never meet at a finite location, meaning the image forms at infinity. This configuration is used in collimators and searchlights to produce parallel beam. Choice B incorrectly suggests the image forms at the focal point, confusing object and image positions—when the object is at the focal point, the image cannot also be there. To identify this special case, check if the object distance equals the focal length; if so, expect parallel exit rays and an image at infinity.

Question 19

1. Real, inverted, and larger than the object (correct answer)
2. Virtual, upright, and larger than the object
3. Virtual, inverted, and smaller than the object
4. Real, upright, and located on the lens surface

Explanation: This question tests understanding of images formed by lenses. When an object is placed between f and 2f from a converging lens, the lens produces a real, inverted, and magnified image. The parallel ray refracts through the far focal point while the center ray continues straight, and these rays converge on the opposite side of the lens beyond 2f. Since the rays actually meet rather than requiring backward extensions, the image is real and can be projected onto a screen. The image appears larger because the converging rays meet farther from the lens than the object distance, and all real images from single lenses are inverted. Choice D incorrectly suggests a real image can be upright and form on the lens surface, combining two impossibilities—real images from single lenses are always inverted, and images never form at the lens plane. For converging lenses, memorize the three zones: inside f gives virtual magnified images, between f and 2f gives real magnified images, and beyond 2f gives real reduced images.

Question 20

1. Real, inverted, and farther from the lens than the object
2. Virtual, upright, and smaller than the object (correct answer)
3. Real, upright, and on the far side of the lens
4. Virtual, inverted, and located on the lens surface

Explanation: This question tests understanding of images formed by lenses. A diverging lens always produces virtual, upright, and diminished images regardless of object position. The center ray passes straight through undeviated, while the parallel ray refracts as if coming from the near focal point, causing all refracted rays to diverge. Since only backward extensions of the diverging rays meet, the image is virtual and forms on the same side as the object. The image appears smaller because the diverging rays make the apparent source closer to the lens than the actual object, and it remains upright as with all virtual images. Choice D incorrectly claims the image is inverted and on the lens surface, showing confusion about both image orientation for virtual images and the impossibility of images forming at the lens plane itself. When analyzing diverging lenses, remember they can only form virtual, upright, reduced images—trace the parallel and center rays to confirm this pattern.