⚛️ Physics Quiz 15: Lenses and Image Formation

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⚛️ Physics · Quiz 015

Apply PHYS-014 refraction to thin lenses and image formation, including real/virtual images and magnification.

Learning goalPredict and calculate image location, orientation, and magnification for ideal thin converging and diverging lenses.

  • 5 questions
  • Foundation
  • Explanations after finishing
Answered 0/5
FoundationWhat does an ideal converging thin lens do to rays that enter parallel to its optical axis?
Need a small nudge?

Use the defining ray rule for a converging lens.

UnderstandingAn object is placed closer to an ideal converging lens than the lens's focal length. What image does the lens form?
Need a small nudge?

For a converging lens, compare the object distance with f and think about whether refracted rays actually meet.

ApplicationAn object is 60 cm from an ideal converging lens with focal length +20 cm. Using 1/f = 1/d_o + 1/d_i, what is d_i?
Need a small nudge?

Solve 1/d_i = 1/f - 1/d_o using the stated sign convention.

InterpretationFor an ideal converging lens, an object moves from a position beyond 2f to a position between f and 2f. What happens to the image?
Need a small nudge?

Use the standard converging-lens ray cases on either side of the 2f object position.

ConnectionAn object is 30 cm from an ideal diverging lens with focal length -15 cm. Using the thin-lens equation and m = -d_i/d_o, which result is correct?
Need a small nudge?

A diverging lens has f < 0. Solve for d_i first, then use the sign and magnitude of m.

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