How can we see the word on the front of this vehicle written correctly? Why is it written the way it is?
Because light waves travel in straight lines an arrow called a ray can be used to show a light wave’s path and direction. We use rays in diagrams to show the direction of light that is reflected by mirrors or refracted by lenses. Review: What is reflection? What is refraction?
A plane mirror is a mirror that has a flat surface. When you look in a mirror you see a virtual image. A virtual image is an image through which light does not travel.
When you look in a plane mirror, your image is: Right side up The same size as the object being reflected Reversed left to right
A concave mirror is a mirror that curves in. (Hint to remember: You go into a cave.) The image formed by a concave mirror depends on three things: the optical axis, focal point, and focal length of the mirror. The focal point is the point in space at which light incident to the mirror and traveling parallel to the principal axis will meet after reflection. Watch video: http://www.physicsclas sroom.com/Class/refln/ u13l3a.cfm#vocab http://www.physicsclas sroom.com/Class/refln/ u13l3a.cfm#vocab
Two rules of reflection for concave mirrors: Any incident ray traveling parallel to the principal (optical) axis on the way to the mirror will pass through the focal point upon reflection. Any incident ray passing through the focal point on the way to the mirror will travel parallel to the principal (optical) axis upon reflection. These two rules of reflection are illustrated in the diagram below.
A concave mirror can form a virtual image (as a plane mirror does), or a real image. A real image is an image through which light passes. Watch the video at the website to see a real image formed. http://www.physicsclas sroom.com/class/refln/ u13l3d.cfm http://www.physicsclas sroom.com/class/refln/ u13l3d.cfm
What does the image look like if the object is more than one focal length from the mirror? The image will be an upside-down, real image. It’s size will depend on it’s distance from the mirror. What does the image look like if the object is less than one focal length from the mirror? The image will be a right-side-up, virtual image that appears larger than the actual object.
What happens to the image if the object is placed at the focal point of the mirror? The incident rays reflect off parallel to the optical axis and no image is formed. Headlights and flashlights use concave mirrors to reflect a powerful beam of light from a light bulb by placing the bulb at the focal point of the mirror. Lighthouses also use concave mirrors.
Convex mirrors are mirrors that curve outward, like the back of a spoon. How does the image appear in a convex mirror? The image formed is a right-side-up, virtual image that is smaller than the actual object.
Convex mirrors are useful because they make images of large areas. Convex mirrors are often used for security in stores and factories. They are also frequently used as side mirrors on cars and trucks.