Unit: Optics
Year: 1994 Question#: 93
Question: A student placed an object at various distances (d0) from a converging lens. The corresponding image distance (di) was measured and recorded in the data table below.
What is the focal length of the lens?
(1 ) 0.10 m
(2 ) 0.15 m
(3 ) 0.20 m
(4 ) 0.30 m
What is this question really asking?
Explanation by: Steven B
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Answer 1
0.10 m
CORRECT
0.10 m is correct because of the formula:
Choose any pair of numbers from the table and plug them into the equation. For example:
The answer you get is 0.10 m. return to top
Answer 2
0.15 m
INCORRECT
0.15 m is incorrect
return to top
Answer 3
0.20 m
INCORRECT
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Answer 4
0.30 m
INCORRECT
0.30 m is incorrect return to top
What's this question really asking?
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The question is asking if you know how to use the thin lens equation and solve for the focal length.
