Define the principal focus of a concave mirror

For these mirrors, we have some important terms like • Center of Curvature • Radius of curvature • Pole of the Mirror • Principal Axis • Focus of the mirror Let's look at them one by one Center of Curvature (C) We can say that the mirror is a part of the hollow sphere The center of this sphere is the Center of Curvature It is represented by the letter C Note: - Center of curvature of Concave mirror is on the front, and of convex mirror is on the back Radius of Curvature The radius of the hollow sphere which the mirror is a part of is the Radius of Curvature It is represented by the letter R Note : - that R = PC Pole of a Mirror(P) Center of the spherical mirror is called Pole It is represented by the letter P Principal Axis A straight horizontal line passing through pole and center of curvature Principal focus For principal focus, let's look at Concave and Convex Mirrors separately Principal Focus (F) of concave mirror The point at which rays parallel to principal axis coming from infinity converge after being reflected from concave mirror is called the principal focus of concave mirror. Principal Focus (F) of convex mirror The point at which rays parallel to principal axis coming from infinity appear to converge after being reflected from convex mirror is called the principal focus of convex mirror. Note: - Focus of convex mirror is behind the mirror, so it is a virtual focus Focal Length It is distance between Pole (P) and Principal Focus (F) It is represented by the let...

(a) Define (i) principal focus of a concave mirror, and (ii) focal length of a concave mirror. Draw diagram to represent the action of a concave mirror on a beam of parallel light rays. Mark on this diagram principal axis, focus F, centre of curvature C, pole P and focal length f of the concave mirror. (a) (i) Principal focus of a concave mirror. The principal focus of a concave mirror is a point on its principal axis to which all the light rays are parallel and close to the axis converge after reflection from the concave mirror. (ii) Focal length of a concave mirror. The focal length of a concave mirror is the distance between its pole and the principal focus

Fortunately, this is one of those questions that sounds harder than it actually is... The "principal focus" for a concave mirror is exactly the same thing as the focal point, which you may have heard of before. If you were to take a concave mirror and shine a whole lot of rays of light straight at it (all parallel to each other), then all of those beams would be reflected by the mirror, and they’d all converge at one point. That point is what’s called the focal point (or the principal focus). Here’s a picture to better show you what I mean: On this picture, the focal point (the principal focus) is labeled with the F. This picture came from the page on concave mirrors. -Tamara (published on 10/22/2007) Mirrors work by changing the direction that light is moving. In a concave mirror, the light gets reflected towards the center. In a convex mirror, the light moves away. To make an image, we can trace a few rays that the light makes and see what happens to them. Let's start with a concave mirror. If the object is far away, the light rays come in, and then bounce and come back together. See the picture below. This is an example of a real image. (Whoops, link lost, but see follow-up for picture.) If the object is very close to the concave mirror or you use a convex mirror, the light doesn't come back together. However, if you look at the light that comes off of the mirror and trace it back while pretending the mirror isn't there, they will come back to a point. This is called a ...

Explanation, • A spherical mirror is a mirror that has the appearance of a spherical surface cut out of a portion. • Two kinds of spherical mirrors are available: concave and convex mirrors. • The principal focus or focal Point of a spherical mirror is on the axis of a mirror or lens where after reflection or refraction rays of light parallel to the axis converge or begin to converge. • If a bunch of rays of light is shined straight at a concave mirror, all of those beams will be mirrored by the mirror and will all meet at one point. That point is called the principal focus or focal point. • In the figure below F is the principal focus.

Hint: Focus means where the light focuses. Light gets converged when it reflects from the surface of a concave mirror whereas it gets diverged when it is reflected from the surface of a convex mirror. Complete answer step by step: Principle focus: When light rays parallel to the principal axis coming from infinity fall on the surface of the concave mirror, it converges at a single point on the principal axis. This point is called ‘Principal Focus of concave mirrors. The principal focus is also referred to as simply focus or focal point. The concave mirror focal point lies in front of the mirror. As shown in above figure, parallel rays coming from infinity converge at principal focus F. Uses of convex mirror: 1. Convex mirrors are used as side mirror in vehicles as they provide wider field of view 2. To eliminate blind spots they are hanged or mounted at the corners of hallways or roads. 3. As convex mirrors diverge the light, it is used in street light for more spread of light. Additional Information: The concave and convex mirrors are two types of curved mirrors. Concave mirrors are used where we want to converge light and convex mirrors are used where we want to diverge the light. The principal focus of convex mirrors lies behind the mirror therefore light appears to be diverging when it gets reflected from the convex mirror. Note: Do not get confused between these two types of mirrors. Many times students get confused between convex and concave mirrors especially about ...

The principle focus of concave mirror is a point on its principle axis to which all the light rays which are parallel and close to the axis, converge after reflection from the mirror. Uses of convex mirrors: 1) Convex mirrors are used in rear view mirror in vehicles because the mirror can diverge a beam of light and create a virtual image.

• The principal focus of a concave mirror is a point on the principal axis at which a light ray parallel to the principal axis converges after reflection. • Light rays that are parallel to the principal axis of a concave mirror converge at a specific point on its principal axis after reflecting from the mirror. This point is known as the principal focus of the concave mirror. • It is denoted by F.