Concave mirrors can do two tricky things — if an object is far away from the mirror, it will appear much bigger than it actually is; if an object is close-up to the mirror, the reflection will be small and upside-down. For more information about how light waves and reflections work, you might like to check out this short video. You are commenting using your WordPress. You are commenting using your Google account.
You are commenting using your Twitter account. You are commenting using your Facebook account. Notify me of new comments via email. Notify me of new posts via email. Search Search for:. You'll also find the real image is smaller than the object while the virtual image is bigger than the object. A quick Google found this article that shows the ray diagrams for real and virtual images. Beginners to optics find the idea of virtual images confusing. A real image can be seen on a screen i. With a virtual image the light rays never come to a focus so there is no place you can put a piece of paper to see the image.
However your eye contains a lens and can bring the diverging light rays to a focus on your retina. Hence your eye can see a virtual image even though it couldn't be projected onto the sheet of paper. You might notice when looking at yourself in a concave mirror that your image flips not at the focal point,f, but at the radius of curvature of the mirror, R.
Applying the lens equation one determines that the image of an object your face for example should flip at the focal point. So what gives? The answer is that the mirror and the lens in your eye act together kind of like a compound telescope. The lens in your eye focuses this virtual object onto the back of your eye and the image is not inverted usually the convex lens in your eye inverts a real image.
Archived Questions Goto Qn. Why is it when I look into a spoon, my reflection is upside down? JSBach Answer has 6 votes. JSBach 22 year member replies Answer has 6 votes.
Basically, because the spoon is curved inward. Rays from the top of your face will be reflected going downwards, rays from the bottom of your face will be reflected going upwards, creating an inverted image. Reversal of image is the property of reflection of a concave mirror. Inwardly curved is concave and outwardly curved is convex. Gnomon Answer has 4 votes. Gnomon 21 year member replies Answer has 4 votes.
The spoon's surface is concave curved inwards. Concave mirrors give reflections upside down, and strangely the image in the mirror appears to be in front of the mirror rather than behind it. This can be explained using complicated diagrams showing rays reflecting and converging, but at the end of the day the only simple answer is 'that's just the way it is'.
A real image occurs when light rays actually intersect at the image, and is inverted, or upside down. A virtual image occurs when light rays do not actually meet at the image. This section will cover spherical mirrors. Spherical mirrors can be either concave or convex. The center of curvature is the point at the center of the sphere and describes how big the sphere is.
These concepts are shown in. Spherical Mirrors : This figure shows the difference between a concave and convex mirror. In a concave mirror, the principal axis is a line that is perpendicular to the center of the mirror. The easiest way to visualize what a image will look like in this type of mirror is a ray diagram. Before that can be done, the focal point must first be defined. This point is half way between the mirror and the center of curvature on the principal axis.
The distance to the focal point from the mirror is called the focal length. We can see from the figure that this focal length is also equal to half of the radius of the curvature. Concave Ray Diagram : This is a ray diagram of a concave mirror. The steps taken to draw are the same as those in a plane mirror. In convex mirrors, the principal axis is the same as in a plane or concave mirror, perpendicular to the center of the mirror.
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