Question

Where do the three rays in a ray diagram start?

A.) at a focal point on the opposite side of the lens
B.) at three different points on the object
C.) at a focal point on the same side of the lens
D.) at a single point on the object

Answer 1

The three rays in a ray diagram start at a single point on the object.

Answer 2

Answer;

D.) at a single point on the object

Explanation;

The three rays in a ray diagram start from a single point on the object.

The three rays are called the the principal rays that are used to determine the location and the size of the image. These are;

• A ray from the top of the object parallel to the principal axis and perpendicular to the lens, will be refracted through the principal focal point.
• A ray that passes through the center of the lens from the top of the object , it will be undeflected.
• A ray through the principal focal point from the top of the object, it will be refracted or proceed parallel to the principal axis upon exit from the lens.