CH 25 (PART 2)- Images and Mirrors in Optics

Object distance (𝑝)

The distance from the object to the mirror.

Image distance (𝑞)

The distance from the image to the mirror.

Real image

An image formed where rays of light actually intersect.

Virtual image

An image formed where rays of light appear to originate.

Upright image

An image that is oriented in the same direction as the object.

Inverted image

An image that is oriented in the opposite direction to the object.

Magnification (𝑀)

The ratio of image height to object height, expressed as 𝑀 = ℎ′/ℎ.

Flat mirror magnification

For a flat mirror, 𝑀 = 1.

Flat mirror image distance

The image is as far behind the mirror as the object is in front, 𝑝 = 𝑞.

Principal Axis

The line that passes through the center of the mirror and the focal point.

Focal Length (𝑓)

The distance from the mirror's surface to the focal point, calculated as 𝑓 = 𝑅/2.

Radius of Curvature (𝑅)

The radius of the sphere from which the mirror is a segment.

Concave mirror case 1

If object distance 𝑝 > 𝑅, the image is real, inverted, smaller than the object, and located on the same side.

Concave mirror case 2

If object distance 𝑝 < 𝑅, the image is virtual, upright, larger than the object, and located on the other side.

Convex mirror

The image is always virtual, upright, smaller than the object, and located on the other side.

Spherical mirror equation

1/𝑝 + 1/𝑞 = 1/𝑓.

Magnification for mirrors

𝑀 = −𝑞/𝑝.

Focal length sign convention

𝑓 is positive for concave mirrors and negative for convex mirrors.

Converging lens

A lens that is thicker at the center than at the rim.

Diverging lens

A lens that is thinner at the center than at the rim.

Ray Diagram for Lens

Ray 1 is drawn parallel to the principal axis and passes through the focal point after refraction.

Converging lens case 1

If the object is outside of the focal point (𝑝 > 𝑓), the image is real, inverted, and on the other side.

Converging lens case 2

If the object is inside the focal point (𝑝 < 𝑓), the image is virtual, upright, and larger than the object.

Diverging lens characteristics

The image is on the same side, virtual, upright, and smaller than the object.

Thin lens equation

1/𝑝 + 1/𝑞 = 1/𝑓 for lenses.

Thin lens magnification

𝑀 = −𝑞/𝑝.

Thin lens example problem

An object is 10 cm from a lens, resulting in an upright image one-fifth as large as the object.