A candle is placed 5 cm in front of a concave mirror with focal length 10 cm (the object is between F and the mirror). What kind of image does the mirror form?
AReal, inverted, magnified — because concave mirrors always form real images
BNo image — a concave mirror cannot form an image when the object is inside the focal length
CVirtual, upright, magnified — because the reflected rays diverge and appear to come from behind the mirror
DVirtual, inverted, reduced — the same as a convex mirror always produces
When an object is between the focal point and a concave mirror, the reflected rays diverge rather than converge — they never meet in front of the mirror. Your eye traces the diverging rays backward to find a virtual image located behind the mirror: upright and larger than the object, like a magnifying mirror. The common misconception is that concave mirrors always make real images — they do only when the object is placed beyond F.
Question 2 Multiple Choice
A store installs a security mirror to monitor a wide area. Which type of mirror is used, and why?
AConcave mirror — it magnifies objects, making distant details easier to see
BConvex mirror — it always produces a virtual, upright, reduced image, giving a wider field of view
CPlane mirror — it produces no distortion and allows accurate size estimation
DConvex mirror — because it can form real images that can be projected onto a screen for recording
Convex mirrors always produce virtual, upright, and reduced images regardless of object position. The reduction in image size means a wide sweep of the scene fits within the mirror's field of view — exactly what security surveillance requires. The cost is that objects appear farther away. Concave mirrors cannot serve this purpose: they produce inverted real images for most object distances and have a narrower, not wider, field of view.
Question 3 True / False
A real image formed by a concave mirror is located in front of the mirror and can be projected onto a screen placed at the image location.
TTrue
FFalse
Answer: True
This is what 'real' means in optics: reflected rays actually converge at the image location. A screen placed there displays a focused image because light physically arrives at that point. Real images form in front of a concave mirror — same side as the object and incoming light — not behind it. Virtual images, by contrast, form where rays only appear to diverge from; no screen can capture them.
Question 4 True / False
A concave mirror usually produces a real image, regardless of where the object is placed.
TTrue
FFalse
Answer: False
A concave mirror produces a real image only when the object is placed beyond the focal point F. When the object is between F and the mirror surface, the reflected rays diverge and form a virtual, upright, magnified image behind the mirror. When the object is exactly at F, the reflected rays emerge parallel and no image forms at all. Object position relative to F completely determines whether the image is real or virtual.
Question 5 Short Answer
Explain the difference between a real image and a virtual image in terms of what the reflected light rays actually do.
Think about your answer, then reveal below.
Model answer: A real image forms where reflected rays actually converge — light physically arrives at that point, so a screen placed there shows a focused image. A virtual image forms where reflected rays appear to diverge from when traced backward — no light actually arrives at that point, so no screen can capture it; only an eye looking into the mirror perceives it.
The distinction is whether the rays actually meet or only appear to meet. For a concave mirror with object beyond F: reflected rays converge in front of the mirror — real image. For a concave mirror with object inside F, or any convex mirror: reflected rays diverge, but their backward extensions meet behind the mirror — virtual image. This determines whether the image can be projected, whether it is inverted or upright, and which sign conventions apply in the mirror equation.