# Exploration

 Explore the Geometric Optics simulation below for several minutes: Try clicking around Try dragging objects Try sliding sliders

Special thanks to the PhET

Now that you have spent several minutes familiarizing yourself with the lens simulation, complete the following multi-choice question. Feel free to use the simulation to help you answer the question. Real Images
• Set the index of refraction to 1.55 and drag the lens so that it is 120 cm from the left hand edge of the simulation. When the object is 22 cm to the left of the (left) focal point of the lens, determine (in comparison to the object) if the image is:
• smaller and upright
• Incorrect! Confirm that the index of refraction is 1.55, and the object is 22 cm to the left of the left focal point.
• larger and upright
• Incorrect! Confirm that the index of refraction is 1.55, and the object is 22 cm to the left of the left focal point.
• larger and inverted
• Absolutely, correct!
• smaller and inverted
• Incorrect! Confirm that the index of refraction is 1.55, and the object is 22 cm to the left of the left focal point.

Tip: Click the "Ruler" checkbox to use a ruler. You can use any radius or diameter. A smaller radius will make it easier to keep both the image and the object visible.

# Reflection

 The image formed in the previous exercise is called a real image because it can be seen with the naked eye or on a screen. Virtual images on the other can not be seen on a screen. They form to the left of (behind) the lens in the simulation above.