#27 - Must Be True

[Administrator]

Complete Question Explanation
(See the complete passage discussion here: lsat/viewtopic.php?t=14311)

The correct answer choice is (E)

A precise prephrased answer to this question would be difficult to produce. Additionally, the concept
reference to “the physics community during the 1930s” is rather broad, making it impossible to focus
on a specific section of the passage in proving the correct answer choice. Due to the high prevalence
of Shell Game answers, however, we must still prove the correct answer with the relevant textual
information.

Answer choice (A): This many seem like an attractive answer, because the neutron bombardment
experiments of uranium were not aimed at proving the earlier theoretical predictions that atoms
could be split. However, we cannot be sure that these theoretical predictions were made before the
1930s.

Answer choice (B): There is no evidence that the physics community of the 1930s reevaluated the
calculations indicating that atoms could be split. A quick glance at the second paragraph reveals that
these calculations were largely ignored, as the neutron bombardment experiments of uranium were
not aimed at proving nuclear fission.

Answer choice (C): Although Fermi and others never identified the by-products of neutron
bombardment of uranium, Hahn and Meitner successfully isolated barium and technetium (lines 41-
43 and 49-53).

Answer choice (D): The second paragraph describes the common view suggesting that a neutron’s
breaking apart a uranium nucleus would be exceptionally difficult to achieve. Just because Meitner
and Hahn finally made the realization that scientists were splitting uranium atoms does not prove
that such atoms were the easiest to split. The comparative difficulty of this task is never discussed in
the passage.

Answer choice (E): This is the correct answer choice. The danger of working with radioactive
substances is one of the reasons why the by-products of the neutron bombardment of uranium were
not immediately identified (lines 33-34). Although it is unclear whether the physics community of
the 1930s was the first to realize this danger, they certainly recognized it (to the detriment of making
progress).

[bk1111]

Hi - I incorrectly picked B. I still don't understand why it's incorrect; if the scientific community accepted the findings of nuclear fission, doesn't it make sense they reevaluated the calculations indicating atoms can split?

[James Finch]

Hi BK,

The issue with answer choice (B) is that while it may be true, we don't know it to be. The passage states that "some theoretical physicists had produced calculations indicating that in principle it should be possible to break atoms apart." (Lines 16-18) We don't know how these calculations related to Meitner's later work that showed that nuclear fission had already occurred in the neutron bombardment experiments. While it may be reasonable to expect that the calculations would be reevaluated, the question asks for what we know.

The only answer that fits that scope is (E), as it can be inferred that the delay in recognizing the radioactive substances being partially caused by "the dangers of working with highly radioactive materials" meant that the scientists working with them were aware of their danger.

Hope this helps!