Spherical mirrors
Beginner
Concave and convex mirrors form real or virtual images.
Concave mirrors converge light and can form real images; convex mirrors diverge light and always give virtual, reduced, upright images (wide view in car mirrors).
Makeup mirrors are concave.
Real images are inverted.
In more detail
Spherical mirrors are concave or convex mirrors with a spherical reflecting surface. Concave mirrors converge light, while convex mirrors diverge it.
Real-world uses
- Concave mirrors focus sunlight in solar furnaces.
- Convex mirrors give wide views in car side mirrors and shop security.
- Car wing mirrors are convex to give a wider field of view, while shaving and makeup mirrors are concave for magnification.
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Frequently asked questions
What is the principal focus?
The point where parallel rays converge after reflecting from a concave mirror.
Why are convex mirrors used for security?
They give a wider field of view, so more of the area is visible.
Why does a convex mirror show more?
It spreads the reflected light out, so the driver sees a wider area behind the car.
Related topics in Optics
Rectilinear propagation · Reflection of light · Plane mirrors · Mirror equation · Magnification of a mirror · Focal length and radius