The visual phenomenon known as refraction alters the appearance of obj

Question

The visual phenomenon known as refraction alters the appearance of objects as they are seen through water. All objects look larger than they actually are, but darker objects appear much more magnified than lighter objects. Hence, a darkly colored pebble on the floor of a swimming pool looks much larger than a white pebble, as long as the two are placed an equal distance from the eye of the viewer.

The conclusion above would be more properly drawn if it were made clear that the

A. darkly colored pebble is assumed to be greater in size than the white pebble

B. darkly colored pebble is assumed to be the same size as the white pebble

C. darkly colored pebble is assumed to be smaller in size than the white pebble

D. pool floor is light in color

E. pool floor is dark in color

winterschool · Answer

The visual phenomenon known as refraction alters the appearance of objects as they are seen through water. All objects look larger than they actually are, but darker objects appear much more magnified than lighter objects. Hence, a darkly colored pebble on the floor of a swimming pool looks much larger than a white pebble, as long as the two are placed an equal distance from the eye of the viewer.

The conclusion above would be more properly drawn if it were made clear that the

A. darkly colored pebble is assumed to be greater in size than the white pebble  Incorrect

darkly colored pebble is already larger than white pebble, so no need to that experiments

B.  darkly colored pebble is assumed to be the same size as the white pebble   Correct

it will proved the premises of the argument

C. darkly colored pebble is assumed to be smaller in size than the white pebble  Incorrect

so, it doesn't not ensure that darkly colored pebble will looks large

D. pool floor is light in color  Incorrect

not a fact

E. pool floor is dark in color  Incorrect

not a fact

mdsaddamforgmat · Answer

IMO B:
Conclusion- a darkly colored pebble on the floor of a swimming pool looks much larger than a white pebble, as long as the two are placed an equal distance from the eye of the viewer.
Question Stem: we need to find the assumptions that will substantiate the above conclusion.
Option B -> clarifies that both stone are of same size further substantiating the conclusion.

gloomybison · Answer

We are given that dark pebble looks larger than white pebble. I am just curious, aren't B & C doing the same thing technically?

desertEagle · Answer

Argument 
Due to refraction, objects appear larger. However, darker objects appear larger than lighter objects when they are at same distance.

Question type 
Find the assumption: Here since darker object appears larger than lighter objects, the author assumes that both are of same size.

A. darkly colored pebble is assumed to be greater in size than the white pebble -->  if it is already greater than white pebble, that will obvious look bigger, because its bigger. Then the argument cant conclude that darker objects looks bigger. May be they look bigger cause they are bigger --> Wrong

B. darkly colored pebble is assumed to be the same size as the white pebble -->  If both are of same size and darker one looks bigger, that means it appear bigger but is not bigger -->  CORRECT 
 
C. darkly colored pebble is assumed to be smaller in size than the white pebble -->  If darker pebble is smaller than white pebble,  "much larger"  will become harder to justify. What if the pebble is too small and still looks just a bit bigger than the white pebble. --> Wrong

D. pool floor is light in color --> Argument is not about pool floor color -->  OUT of scope --> Wrong

E. pool floor is dark in color --> Argument is not about pool floor color -->  OUT of scope --> Wrong

VerbalBot · Answer

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The visual phenomenon known as refraction alters the appearance of obj

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The visual phenomenon known as refraction alters the appearance of obj

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