Mirrors And Reflections
Key Notes :
1. What is a Mirror?
- A mirror is a smooth surface that reflects light.
- Mirrors are typically made of glass with a shiny metallic coating, such as silver or aluminum, on the back.
2. Types of Mirrors:
- Plane Mirrors: Flat mirrors that reflect images without distortion. Examples include bathroom mirrors.
- Curved Mirrors: These can be concave (curved inward) or convex (curved outward).
- Concave Mirrors: Can magnify objects and are used in tools like telescopes.
- Convex Mirrors: Spread light rays and are often used in car side mirrors for a wide view.
3. What is Reflection?
- Reflection occurs when light bounces off a surface, like a mirror.
- The angle at which the light strikes the mirror is equal to the angle at which it bounces off. This is known as the law of reflection.
- The two angles (the angle of incidence and the angle of reflection) are always equal.
4. How Reflections Work:
- When light hits a smooth surface (like a mirror), it bounces back in a predictable direction, creating a reflection of whatever is in front of the mirror.
- The image seen in a plane mirror is always upright, the same size as the object, and reversed left to right.
5. Virtual and Real Images:
- Virtual Images: These are formed when light rays appear to meet, but do not actually converge. The image seen in a plane mirror is a virtual image (appears behind the mirror).
- Real Images: These are formed when light rays actually converge, such as in a concave mirror.
6. Uses of Mirrors:
- Plane Mirrors: Used in homes, bathrooms, and for decorative purposes.
- Concave Mirrors: Used in makeup mirrors, flashlights, and optical devices.
- Convex Mirrors: Used for security (in stores), car mirrors, and street signs to see wider areas.
7. Important Terms:
- Incident Ray: The ray of light that strikes the mirror.
- Reflected Ray: The ray that bounces off the mirror.
- Normal: A line perpendicular to the surface of the mirror at the point of incidence.
Let’s practice!
