values!!

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values!!

by clueless_me » Thu Oct 07, 2010 9:33 am
Although in classical mechanics a physicist can definitely predict both the position and the velocity of an object, in ordinary quantum mechanics certainty in predicting one of those values comes only at the expense of uncertainty about the other.
(A) certainty in predicting one of those values comes only at the expense of uncertainty about the other
(B) certainty in predicting one value comes only at the expense of uncertainty about another
(C) predicting one of those values definitely is Anly at the expense of the other' s uncertainty
(D) only at the expense of uncertainty about another value can you predict one of those values with certainty
(E) If you definitely predict one of those values it is only at the expense of your uncertainty about the other

[spoiler] A
but pls explain why B is wrng.... its making sense even w/o "those"[/spoiler]
Source: — Sentence Correction |

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by shovan85 » Thu Oct 07, 2010 9:41 am
Why B is wrong?

You cannot discard "those of". Here those means "position and velocity" (inherited from not underlined part).
The underlined section say that "certainty in predicting position comes only at the expense of uncertainty about velocity"
or
"certainty in predicting velocity comes only at the expense of uncertainty about position "

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by niksworth » Thu Oct 07, 2010 10:43 am
1. those is required to make the reader understand that quantum mechanics is talking about the same two values and not any other values.

2. If we have only two values, we have to use one and the other and not one and the another.
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