Ray Optics: Refraction and Lenses
Refraction and Lenses: Audio Guided Solution
During the Finding Smiley Lab, Tyrone and Mia place a small light bulb at various distances from a converging lens. The light bulb has a smiley face marked on one of its side. Their goal is to locate the images of the light bulb by projecting the refracted light onto a note card.
The lens is known to have a focal length of 20. cm. Predict the image distances which Tyrone and Mia will likely determine when the smiley face is located a distance of …
a. … 60. cm from the lens.
b. … 40. cm from the lens.
c. … 30. cm from the lens.
d. … 10. cm fron the lens.
Audio Guided Solution
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b. 40. cm from the lens (to the right)
c. 60. cm from the lens (to the right)
d. 20. cm from the lens (to the left, corresponding to a dimage of -20. cm)
Habits of an Effective Problem Solver
- Read the problem carefully and develop a mental picture of the physical situation. If necessary, sketch a simple diagram of the physical situation to help you visualize it.
- Identify the known and unknown quantities and record them in an organized manner. Equate given values to the symbols used to represent the corresponding quantity - e.g., do = 24,8 cm; di = 16.7 cm; f = ???.
- Use physics formulas and conceptual reasoning to plot a strategy for solving for the unknown quantity.
- Identify the appropriate formula(s) to use.
- Perform substitutions and algebraic manipulations in order to solve for the unknown quantity.
Read About It!
Get more information on the topic of Refraction and Lenses at The Physics Classroom Tutorial.
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