PHY 112 NATIONAL INSTITUTE OF SCIENCE AND TECHNOLOGY
FACULTY OF PURE AND APPLIED SCIENCES DEPARTMENT OF
PHYSICS| FINAL SPRING EXAM 2026
CONCAVE AND CONVEX MIRRORS
Ray Optics, Image Formation, Mirror Equation, and Applications in Real Life
Systems
What is a concave mirror?
-A concave mirror is a mirror that caves inward.
-It is also known as a converging mirror.
-These mirrors reflect light into one point. (One focal point)
What is a convex mirror?
-A convex mirror is a mirror that's surface protrudes outwards- toward the light source.
-It is also known as a diverging mirror.
-These mirrors reflect light outwards.
What equation is used to determine the focal length of the mirror? (spherical mirror)
F = R/2
(R = the radius of curvature)
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, What equation is used to find the location of the image or object AND can be used to find the
focal point/length?
1/d(o) + 1/d(i) = 1/f
-d(o) = object distance
-d(i) = image distance
-f = focal length
What equation is used to find there magnification of the image?
m = h(i)/h(o) = -d(i)/d(o)
h(o) = obj. height
h(i) = img. height
How do you tell if an image is real or virtual?
In a concave mirror:
-Image is real if the distance of the object from the mirror is greater than the focal length
-Virtual if it is less than the focal length.
*Convex mirrors = only virtual
2|Page
FACULTY OF PURE AND APPLIED SCIENCES DEPARTMENT OF
PHYSICS| FINAL SPRING EXAM 2026
CONCAVE AND CONVEX MIRRORS
Ray Optics, Image Formation, Mirror Equation, and Applications in Real Life
Systems
What is a concave mirror?
-A concave mirror is a mirror that caves inward.
-It is also known as a converging mirror.
-These mirrors reflect light into one point. (One focal point)
What is a convex mirror?
-A convex mirror is a mirror that's surface protrudes outwards- toward the light source.
-It is also known as a diverging mirror.
-These mirrors reflect light outwards.
What equation is used to determine the focal length of the mirror? (spherical mirror)
F = R/2
(R = the radius of curvature)
1|Page
, What equation is used to find the location of the image or object AND can be used to find the
focal point/length?
1/d(o) + 1/d(i) = 1/f
-d(o) = object distance
-d(i) = image distance
-f = focal length
What equation is used to find there magnification of the image?
m = h(i)/h(o) = -d(i)/d(o)
h(o) = obj. height
h(i) = img. height
How do you tell if an image is real or virtual?
In a concave mirror:
-Image is real if the distance of the object from the mirror is greater than the focal length
-Virtual if it is less than the focal length.
*Convex mirrors = only virtual
2|Page
