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Ch.1 - Matter, Measurement & Problem Solving
Tro - Chemistry: A Molecular Approach 4th Edition
Tro4th EditionChemistry: A Molecular ApproachISBN: 9780134112831당신이 사용하는 게 아니라요?교과서 변경
1장, 문제 79b

Which numbers are exact (and therefore have an unlimited number of significant figures)? b. 12 in = 1 ft

검증된 단계별 안내
1
Identify the type of numbers involved in the conversion factor.
Recognize that conversion factors between units within the same measurement system (e.g., inches to feet) are defined values.
Understand that defined values are considered exact numbers.
Conclude that exact numbers have an unlimited number of significant figures.
Therefore, the numbers in the conversion factor '12 in = 1 ft' are exact.

비슷한 문제에 대한 검증된 영상 답변:

이 영상 해법은 위 문제에 도움이 된다고 튜터들이 추천한 것입니다.
영상 길이:
1m
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주요 개념

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Exact Numbers

Exact numbers are values that are counted or defined quantities, which have no uncertainty and therefore an infinite number of significant figures. Examples include the number of students in a classroom or defined conversion factors, such as 12 inches in a foot. Because they are not measured, they do not contribute to the uncertainty in calculations.
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가이드 코스
00:46
Number of Electrons in Shells

Significant Figures

Significant figures are the digits in a number that contribute to its precision, including all non-zero digits, any zeros between significant digits, and trailing zeros in the decimal portion. Understanding significant figures is crucial for accurately reporting measurements and results in scientific calculations, as they reflect the precision of the data.
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가이드 코스
01:09
Significant Figures Example

Unit Conversion

Unit conversion involves changing a quantity expressed in one unit to another unit, often using conversion factors. In the example given, the relationship of 12 inches equaling 1 foot is a defined conversion factor, which is exact. This means that when performing calculations involving unit conversions, the exact nature of these factors ensures that the precision of the result is maintained.
추천 영상:
가이드 코스
01:56
Conversion Factors