Lec1 Conversion Factors, Sig Figures, Sc Notation

What is a conversion factor?

• A ratio of equivalent values of a quantity expressed in same units.

• A ratio of equivalent values of a quantity expressed in different units.

• A quantity expressed in different units.

• A quantity expressed in same units.

What is the conversion factor for

s/min?

Answer explanation

60 s/1 min -> 60s/min

What is the conversion factor for min2/s2?

Answer explanation

(1 min)2/ (60 s)2 -->

1 min2/3600s2

What is the conversion factor for m3/cm3?

Answer explanation

(1 m)^3/(1 x 10^2 cm)^3

--> 1 m^3/1 x 10^6 cm^3

Write the scientific notation and significant figure for 0.03500

• SN: 0.035

  SF: 2

• SN: 0.035

  SF: 4

• SN: 3.5 x 10^2

  SF: 2

• SN: 3.500 x 10^-2

  SF: 4

Answer explanation

SN: 3.500 x 10^-2

SF: 4

Trailing zeros (0) in the decimal portion ONLY are significant

Round 3.78721 to three significant figures.

• 3.78

• 3.79

• 3.78 x10^1

• 3.79 x 10^1

Round 726.835 to five significant figures

• 7.3 x 10^5

• 7.2683 x 10^10

• 726.83

• 726.84

Round off at the 5: 2.0495

• 2

• 2.049

• 2.050

• 2.05

Answer explanation

2.050 - the 9 from 2.0495 rounds off to a ten (not a zero), so the correct answer is 2.050, not 2.05.