Chapter 2: Measurements and Problem Solving

Flashcards about Measurements and Problem Solving

What is a measurement?

A determination of quantity.

What is a unit in measurement?

A standard of measure.

Why are qualitative descriptions not enough in scientific testing?

Scientific testing requires quantitative measurements for accuracy and precision.

What is accuracy?

How close a measurement is to the accepted value.

What is precision?

How well numbers are grouped together based on the method used.

What is the rule for non-zero digits in significant figures?

Any non-zero number is significant and counts.

What is the rule for zeros in front of non-zero digits in significant figures?

Any zero in front of a non-zero number never counts.

What is the rule for zeros between non-zero digits in significant figures?

Any zero between two non-zero numbers always counts.

What is the rule for zeros behind a non-zero digit in significant figures?

Zeros behind a non-zero number only count if there is a decimal point.

When multiplying and dividing measurements, how many significant digits should the result have?

The result should have the same number of significant digits as the least significant measurement.

What is the proper procedure for writing numbers in scientific notation?

Move the decimal behind the first non-zero number, count the spaces, and place as power of 10; if the number is less than 10, make the power negative; if greater than 10, make the power positive; round for significant figures.

What is the multiplier for the prefix kilo (k)

( 10³ ) or 1,000

What is the prefix for the symbol M

Mega

What are the fundamental SI units for length, mass, time, and temperature?

Length: meter (m); Mass: kilogram (kg); Time: second (s); Temperature: Kelvin (K).

What is the SI unit for length?

The meter (m).

What is the SI unit for volume?

m³.

What is the SI unit for mass?

kg (kilogram).

What is density?

Mass per unit volume (Density = Mass / Volume)

What is a conversion factor?

A ratio derived from the equality between two different units that can be used to convert from one unit to another.

What is dimensional analysis?

A method using conversion factors to change units; arranging conversion factors so that unwanted units cancel, leaving only the desired unit.

What are the fundamental SI units for length, mass, time, and temperature?

Length: meter (m); Mass: kilogram (kg); Time: second (s); Temperature: Kelvin (K).

What is the SI unit for length?

The meter (m).

What are the SI base units for the amount of substance, electric current, and pressure?

Amount of substance: mole (mol); Electric Current: ampere (A); Pressure: Pascal (Pa).