Units and Significant Digits. Standards of Length, Mass and Time MKS System (SI units) Length –...

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Units and Significant Digits

Transcript of Units and Significant Digits. Standards of Length, Mass and Time MKS System (SI units) Length –...

Page 1: Units and Significant Digits. Standards of Length, Mass and Time MKS System (SI units) Length – Meter ( 1/299,792,458 distance light travels in a vacuum.

Units and Significant Digits

Page 2: Units and Significant Digits. Standards of Length, Mass and Time MKS System (SI units) Length – Meter ( 1/299,792,458 distance light travels in a vacuum.

Standards of Length, Mass and Time

MKS System (SI units)• Length – Meter ( 1/299,792,458 distance light

travels in a vacuum in one second• Mass – Kilogram (Mass of the International

Prototype Kilogram, a/k/a “Le Grande K”)• Time – Second (9,192,631,770 periods of the

radiation from cesium-133)

Page 3: Units and Significant Digits. Standards of Length, Mass and Time MKS System (SI units) Length – Meter ( 1/299,792,458 distance light travels in a vacuum.

Prefixes for SI

10-24 yocto

10-21 zepto

10-18 atto

10-15 femto

10-12 pico

10-9 nano

10-6 micro

10-3 milli

10-2 centi

10-1 deci

1024 yotta

1021 zetta

1018 exa

1015 peta

1012 tera

109 giga

106 mega

103 kilo

102 hecto

101 deka

Page 4: Units and Significant Digits. Standards of Length, Mass and Time MKS System (SI units) Length – Meter ( 1/299,792,458 distance light travels in a vacuum.

Significant DigitsSignificant Figures (Sig Figs)

123.4 Four Significant Digits

0.0012 Two Significant Digits

1,500 ? Significant Digits

1.50 x 103 Three Significant Digits

Page 5: Units and Significant Digits. Standards of Length, Mass and Time MKS System (SI units) Length – Meter ( 1/299,792,458 distance light travels in a vacuum.

Adding/Subtracting

123.4 + 456 = 579

123.4 + 4.56 x 106 = 4.56 x 106

Only significant to the limit of any single term

Page 6: Units and Significant Digits. Standards of Length, Mass and Time MKS System (SI units) Length – Meter ( 1/299,792,458 distance light travels in a vacuum.

Multiplying/Dividing

123.4 x 456 = 5.63 x 104

Only significant to the smallest number of significant digits in any single term