You are here:

# Physics/Lenses

Question
1. Draw the ray diagrams for the four following situations. In each case, state if the image is real or virtual, inverted or upright, smaller or larger than the object.

The images are in the description.

Converging Lenses
A - draw a light ray parallel to the principle axis until it strikes the lens and then passes through the converging lens until it passes through the focus.
B - draw a light ray through the vertex V of the lens which passes through undeflected since the center of the lens is essentially a parallel faced pane of glass.
There the two light rays meet is where the final image will be found. This image is real since the light rays actually converge at this point. The resulting image will be inverted relative to the object and can be projected on a screen.
C - again a light ray parallel to the principle axis will refract through the focus.
D - again a light ray to the vertex passes through undeflected.
In this case the resulting light rays diverge rather than converge as in the previous diagram. To determine the position of the image "backtrack" the light rays [use dotted lines rather than solid lines to indicate that the light rays don't really go there!] until they meet, in this case on the same side of the lens as the object. The resulting image is virtual since the light rays do not really converge, the resulting image is erect and the resulting image CANNOT be projected on a screen.

Physics