http://www.ck12.org Chapter 5. Energy
Summary
- When a mirror reflects light, it forms an image. An image is a copy of an object formed by reflection (or
refraction). A real image is a true image that forms in front of a mirror where reflected light rays actually
meet. A virtual image appears to be on the other side of the mirror and doesn’t really exist. - Most mirrors are plane mirrors that have a flat reflective surface. A plane mirror forms only virtual, right-side
up, and life-sized images. - A concave mirror is shaped like the inside of a bowl. The type of image it forms depends on where the object
is relative to the focal point. The image may be real, upside down, and reduced in size; or it may be virtual,
right-side up, and enlarged. - A convex mirror is shaped like the outside of a bowl. It forms only virtual images that are right-side up and
reduced in size relative to the object.
Vocabulary
- concave: Curving inward like the inside of a bowl.
- convex: Curving outward like the outside of a bowl.
- image: Copy of an object that is formed by reflected or refracted light.
- reflection: Bouncing back of waves from a barrier they cannot pass through.
Explore More
At the following URL, review how a plane mirror forms an image, and watch the animation. Then answer the
multiple choice questions below. http://www.physicsclassroom.com/mmedia/optics/ifpm.cfm
- A plane mirror forms an image where the reflected rays
a. divide.
b. separate.
c. begin.
d. intersect. - The image formed by a plane mirror appears to be
a. on the same side of the mirror as the object.
b. on the opposite side of the mirror from the object.
c. either on the same side or the opposite side, depending on the distance of the object from the mirror.
d. on both sides of the mirror, regardless of the distance of the object from the mirror. - The distance from the object to a plane mirror equals the distance from the mirror to the
a. image.
b. incident ray.
c. reflected ray.
d. normal. - Anyone who sees the image formed by a plane mirror is sighting at the same image
a. size.
b. line.
c. distance.
d. location.