Ray Diagrams in Convex mirrors. Optics SNC 2DO. Convex Mirrors. Reflecting surface curves outward Convex mirrors have their focal point and centre behind the mirror M ake a small, virtual image of the original object . Drawing Ray Diagrams – convex mirrors.
Ray Diagrams in Convex mirrors
Reflecting surface curves outward
Convex mirrors have their focal point and centre behind the mirror
Make a small, virtual image of the original object
Rule #1 - In the diagrams the rays will be extended behind the mirror as dotted lines to be able to show how they pass through F or C
Rule #2: draw the ray coming off of the tip of the object parallel to the principle axis
- when it hits the mirror, it bounces off so that a dotted line drawn behind the mirror will pass through the focal point
Rule #3- This ray comes off of the tip of the object and to the thecentre.
Where it hits the mirror it will bounce back, but I draw a dotted line behind the mirror to show where the ray would have gone.
The image will appear at the point where the 2 dotted lines connect.
1: A convex mirror has a radius of 20 cm. An object is placed 30 cm in front of the mirror. Determinewhere the image will appear.
2: For the same situation from Example 1, determine how tall the image is if the object is 5.0 cm tall. Also determine the magnification.
Since the radius is 20 cm (which is the distance from the mirror to the centre), and since the focal point is half ways in between and negative for a convex mirror, f = -10 cm. Since di is negative, it appears behind the mirror as a virtual image.
Since di is negative, it appears behind the mirror as a virtual image.
Read pgs.431-438 – do Practice Problems (#1-7) on pg. 436 and answer questions # 1-8 on pg. 438.