2.1- Units of Measurement
When does water freeze on the Kelvin Scale?
273 K.
When does water boil on the Kelvin scale?
373 K.
What is the common unit for density?
Grams Per Cubic Centimeter.
The temperature of an object is a measure of what?
How hot or cold the object is relative to other objects.
A base unit is ___ of other units?
Independent.
In how much time do many chemical reactions take place?
Less than a second.
What does the cubic centimeter not work well with?
Liquids or for solids with irregular shapes.
Density
Mass/Volume.
A milliliter is equal in volume to what?
One cubic centimeter.
One liter has about the same volume as?
One quart.
What is the boiling point in Celsius?
One-Hundred degrees Celsius.
The kilogram is defined by the what?
Platinum-Iridium metal cylinder.
Meter
SI base unit for length.
Kilogram
SI base unit for mass.
Second
SI base unit for time.
How many base units are in SI?
Seven.
What does the cubic centimeter work well with?
Solid objects with regular dimensions.
How do you convert from Kelvin to Celsius?
Subtract 273.
What is the revised system of the Metric System called?
Système Internationale d'Unités (abbreviated SI).
What did French Scientists adopt in 1795?
The Metric System.
Kelvin
The SI base unit of temperature.
Liter
The metric unit for volume equal to one cubic decimeter.
Who devised the Kelvin scale?
William Thomson, A Scottish physicist and mathematician, who was known as "Lord Kelvin".
What is the freezing point in Celsius?
Zero degrees Celsius.
The distance that light travels through a vacuum in 1/299,792,458 of a second is what?
A Meter.
Base Unit
A defined unit in a system of measurement that is based on an object or event in the physical world.
Density
A ratio that compares the mass of an object to its volume.
Vacuum
A space containing no matter.
Derived Unit
A unit that is defined by a combination of base units.
How many pounds is a kilogram equal to?
About 2.2 pounds.
How do you convert from Celsius to Kelvin?
Add 273.
The Celsius scale was devised by who?
Anders Celsius, a Swedish astronomer.
How did Celsius establish his scale?
By using the temperatures at which water freezes and boils to establish his scale because the temperatures are easy to produce.
How do you classify an object as either hot or cold?
By whether or not heat flows from you to the object, or from the object to you.
What clocks are more reliable than those used to measure time?
Cesium Clocks.
Liters are used to measure what?
The amount of liquid in a container of bottled water or a carbonated beverage.
What is the derived unit for volume?
The cubic meter, which is represented by a cube whose sides are all one meter in length.
What is the physical standard used to establish the length of a second?
The frequency of microwave radiation given off by a cesium-133 atom.
What did an international committee of scientists do in 1960?
They met to update the Metric System.
What are some familiar quantities that are expressed in base units?
Time, Length, Mass, and Temperature.
The platinum-iridium metal cylinder is stored in a what?
Triple bell jar to keep air away from the metal.
