Touch and drag the [b]blue object point O[/b] or the [b]focus point X[/b] (along the x-axis).

Touch and drag the object point (blue o). [br]1. How does the little black point on the lens move? What is its definition? [br]What are the properties of the determining rays? How do we find the image point ?[br]2. How high can I drag the blue point? Why do you think the applet won't let me drag it higher?[br]3. How low can I drag the blue point? Why do you think the applet won't let me drag it lower? [br]4. How close to the lens can I move it before the image point flips?[br]If you are having trouble answering this question, click and drag the focus point (red x).[br][br](Remember that "thin" means we ignore refraction within the lens itself.)