Name: measurement precision and significant figures
Uploaded: 2023-04-30T10:48:20.000Z
Duration: 1 min 44 s
Channel: JoVE

Ölçümün kesinliği iki faktöre bağlıdır: ölçümdeki basamak sayısı ve kullanılan aletin hassasiyeti.
Ölçülen bir miktarda, son belirsiz rakam da dahil olmak üzere tüm rakamlara anlamlı rakamlar denir ve belirli kurallar kullanılarak belirlenebilir.
Sıfır olmayan herhangi bir rakam ve sıfır olmayan iki rakam arasında yer alan tüm sabit sıfırlar önemlidir. Örneğin, 28'in iki anlamlı rakamı varken, 26.25'in dört ve 208'in üç rakamı vardır.
Baştaki sıfırlar, yalnızca ondalık noktayı buldukları için hiçbir zaman önemli değildir. Örneğin, 0.00208'in üç önemli rakamı vardır. Bu tür nicelikler üstel gösterimler kullanılarak ifade edilebilir. Böylece, 0.00208 10−3 × 2.08 olarak yazılabilir.
Sondaki sıfırlar yalnızca ondalık biçimli sayılarda anlamlıdır. 2200'ün sonda iki sıfırı ve iki anlamlı rakamı vardır, oysa 2200.0 ve 2200.1'in her ikisinde de 5 anlamlı rakam vardır.
Ondalık noktası olmayan miktarlar için, sondaki sıfırların önemi belirsiz hale gelir. Böylece, 2200 2.2 × 103 iki anlamlı rakam veya 2.20 x 103 üç anlamlı rakam ile yazılabilir.

anlamlı rakamlar İçin kurallar

Herhangi bir ölçümde, ölçüm aracının hassasiyeti önemli bir faktördür. Örneğin, bir sıradan cetvel uzunluğu en yakın milimetreye kadar ölçebilir; diğer yandan bir kalemmetre, uzunluğu en yakın 0.01 mm'ye kadar ölçebilir. Bu nedenle, kalemmetre son derece küçük uzunluk değişikliklerini ölçebildiği için daha hassas bir ölçme aracıdır. Ölçüm aracı daha hassas olduğunda ölçümler daha doğru olacaktır.

Vurgulanması gereken bir nokta, ölçülen değerleri temsil ettiğimizde, son basamağın ölçüm yapan kişi tarafından bir şekilde hesaplandığıdır. Örneğin, bir cetvelle bir çubuğun uzunluğunu ölçen bir kişi, çubuğun 13.2 cm ile 13.3 cm arasında olduğunu fark eder ve bu durumda son basamağın değerini tahmin etmek zorundadır. Anlamlı rakamlar kuralı, bir ölçümde yazılan son basamağın, belirsizlikle birlikte ilk basamak olduğudur. Bir değerdeki anlamlı basamak sayısını belirlemek için sola doğru ilk ölçülen değerden başlayın ve sağa doğru yazılan son basamağa kadar olan basamak sayısını sayın. Anlamlı rakamlar, bir değeri ölçmek için kullanılan ölçme aracının hassasiyetini temsil eder.

Metin, <a href="https://openstax.org/books/university-physics-volume-1/pages/1-6-significant-figures">Openstax, University Physics Volume 1, Bölüm: 1.6 Anlamlı Rakamlar </a> adresinden alınmıştır.

Anlamlı Rakamlar İçin Kurallar

Herhangi bir ölçümde, ölçüm aletinin hassasiyeti önemli bir faktördür. Örneğin sıradan bir cetvel, uzunluğu en yakın olana kadar ölçebilir ...

Education

JoVE Core

Physics

Fizik

Unit 1

Ünite 1

Units, Dimensions, and Measurements

Birimler, Boyutlar ve Ölçümler

KEY TERMS AND CONCEPTS

TEMEL TERİMLER VE KAVRAMLAR

Rules for Significant Figures

measurement precision and significant figures

Measurement precision depends on the tool used, and significant figures show that precision. A ruler can measure length to the closest millimeter. A caliper can measure length to the nearest 0.01 mm, so it gives a more precise measurement because it can detect very small changes in length.

When a value is written from a measurement, the last digit is not exact. The person making the measurement must estimate that digit. For example, a stick that seems to fall between 13.2 cm and 13.3 cm must be recorded with a guessed last digit.

The last digit in a measurement is the first digit with some uncertainty. To find the number of significant figures, start with the first measured value on the left and count through the last digit written on the right. Significant figures show how precise the measuring tool was when the value was recorded.

Measurement Precision and Significant Figures

measurement-precision-and-significant-figures

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rules for significant figures

Measurement precision depends on the tool used, and significant figures show that precision. A ruler can measure length to the closest millimeter. A caliper can measure length to the nearest 0.01 mm, so it gives a more precise measurement because it can detect very small changes in length. When a value is written from a measurement, the last digit is not exact. The person making the measurement must estimate that digit. For example, a stick that seems to fall between 13.2 cm and 13.3 cm must...

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Rounding Rules for Significant Figures

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key terms and concepts

Learn how ruler and caliper precision affects measurements and how to count significant figures from the first measured digit to the uncertain last digit.

Measurement Precision and Significant Figures | JoVE K12

physics

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Measurement Precision and Significant Figures

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