# Can You Tell What Kind of Measurement This Is?

Tasha Moore

Image: MirageC / Moment / Getty Images

All things can be measured: light, wind, force, temperature ... you name it! That's the premise for this fun batch of educational questions. See if you can name as many measurements as possible on this clever quiz.

Science is such an exact, well, science. The International System of Units ensures that no matter where in the world folks are crunching numbers, all quantities and results match up perfectly. Every so often a bit of tweaking occurs and measurements are re-calibrated. It's all done to make everyone's analytical lives a little easier. Anything that makes math easier is always a good thing, correct?

The International System of Units is the modern metric system and the most widely used system of measurement. The abbreviation "S.I." is short for the French "Systeme International." There are base units, such as second (for time), meter (for length), and ampere (for electric current). Then there are derived units of measurement. We've included quite a few derived units on this test. How well can you reckon the differences?

# High-end LCD computer monitors can refresh at a rate as low as 4.16 milliseconds. What do milliseconds measure?

A megasecond is one billion seconds, and a millisecond is one thousandth of a second. A nanosecond is one billionth of a second, and Planck time is the smallest unit of measurement. Planck time is the time that it takes for light to travel one Planck length.

# What does centigrade measure?

The Celsius temperature scale is also known as the centigrade temperature scale because of the 100-degree intervals between the freezing point at the 0 degrees and the boiling point at 100 degrees. The Swedish astronomer Anders Celsius developed the scale in 1742.

# The average smartphone battery holds a charge of 3,000 mAh, or milliampere-hour. What does an ampere measure?

An ampere is a basic unit of electric current in the International System of Units (SI). The ampere was named for French physicist and mathematician Andre-Marie Ampere, and it expresses a stream of one coulomb of electricity per second.

# Two moles of hydrogen and one mole of oxygen comprise one mole of water. What does a mole measure?

Mole is also written as "mol" in chemistry, and is the unit used for measuring sizable quantities of of small particles such as atoms and molecules. The number of particles in one mole is the same for all substances.

# On average, human breathing registers 10 decibels. What do decibels measure?

Decibel is the unit of measurement for sound used to describe electrical signals, and it is expressed as a proportion between two tangible quantities, usually electrical and acoustical power. Decibel also measures sound intensity.

# One calorie is equal to 4.184 joules. What does a joule measure?

Joule is a measurement of energy derived when one newton force acts on an object in the same motion direction through one meter of distance. Joule also represents the amount of heat energy released when one ampere of electric current flows through an electrical resistance of one ohm per second.

# One horsepower equals what is required to lift 550 pounds a distance of one foot in one second. What does horsepower measure?

Horsepower (hp) is the unit measurement for power, or the rate at which work is done. It has been defined as the weight that a horse could raise 1 foot in 1 second. One horsepower is equal to 746 watts.

# What does calorie measure?

Calorie is the amount of heat necessary to raise the temperature of 1 milliliter of water 1 degree Celsius, from 14.5 degrees to 15.5 degrees Celsius. Calories measure food energy and the stored energy of living beings.

# A lens that has a diopter of +2 has a focal length of 500 millimeters. What does diopter measure?

Diopter, or dioptre, describes the optical power of a given lens or any curved mirror. Diopter is equal to the reciprocal, or the inverse, of the focal length (in meters). Diopter equals 1000 divided by focal length (in millimeters).

# What does a farad measure?

A farad is equal to a capacitor's capacitance, where one coulomb causes a potential difference of one volt. Electrical capacitance is the capability to maintain a charge. The unit is named for English scientist Michael Faraday.

# One disintegration per second equals one becquerel. What does "disintegration" refer to?

The becquerel measures the activity of a given quantity of radioactive substance where one nucleus decays every second. Nucleus decay amounts to one spontaneous transition. The becquerel is named for French physicist Antoine Henri Becquerel.

# What does the siemens measure?

Regarding a direct current, siemens conductance is the inverse of the resistance measured in ohms, where siemens equals amperes per volts. Siemens for an alternating current is the inverse (in ohms) of the total opposition which a circuit (whole or part) exhibits to electrical current.

# Volt defines the size of a force that sends electrons through a circuit. What is volt a unit of?

Volt is the difference of electrical potential, electromotive force or potential difference between two points in a conductor carrying one ampere current, where the released power between the two points is one watt. This unit is named for Italian scientist Alessandro Volta.

# What does a henry measure?

Henry is a unit that measures either mutual inductance or self-inductance. In the case of mutual inductance, one henry equals the value of two coils positioned so that an electromotive force of one volt is generated in one coil when the current in the other coil is changing one ampere per second.

# One standardized paper bale equals 10 reams. What does a bale measure?

A bale is a large bundle of identical individual items tightly bound to facilitate weighing, storage, cataloging, sale or transport. Cotton, paper and hay quantities are measured by the bale. One ream of paper totals 500 sheets of paper.

# A half-dozen eggs equals six eggs. What does the dozen unit measure?

In earlier times, a dozen of 12 was a practical way to quantify a group of easy-to-count and carry loose identical items. The word "dozen" comes from the Latin "duodecim," which means "twelve."

# What does a pascal measure?

Pascal (Pa) measures pressure as one kilogram per meter per second squared or one newton per square meter. Pascal also measures stress, Young's modulus (numerical constant) and tensile strength, which is the maximum load that a material can sustain without breaking divided by the material's initial cross-sectional area.

# At Earth's gravity of 9.80665 meters per second squared, one kilogram of mass exerts 9.8 newtons. What does a newton measure?

One newton describes the force needed to give one kilogram of mass an acceleration of one meter per second squared in the direction of an applied force. The unit is named for English scientist and mathematician Sir Isaac Newton.

# What does a hertz measure?

Hertz is a derived unit of frequency in the S.I. system that equals one cycle per second. Periodic phenomena are measured by hertz, which gauges if one cycle of the same phenomenon repeats in a one-second period. A gigahertz equals 1000 million hertz. The unit is named for German physicist Heinrich R. Hertz.

# New York's Yankee Stadium spans 24 acres in the Bronx. What does an acre measure?

An acre is equal to 160 square rods (old English measurement), 4,840 square yards or 43,560 square feet. A hectare is a unit of area that equals 100 ares (100 square meters), 10,000 square meters or 2.471 acres.

# What does a weber quantify?

A weber was named for German physicist Wilhelm Eduard Weber. One weber equals 1 volt-second. A weber expresses the flux quantity produced within itself by an electromotive force of 1 volt as the flux reduces to zero at a consistent rate within 1 second.

# Jalapeno peppers measure between 5,000 and 9,000 Scoville heat units. What does a Scoville heat unit measure?

The Scoville scale measures the relative spiciness or heat of chili peppers and other spicy foods. Pharmacist Wilbur Scoville devised the Scoville heat unit (SHU) in his pursuit to create a heat-generating ointment. The SHU is based on the amount of dilution necessary to eliminate the "hotness" of a substance.

# What does a micromort measure?

Micromort measures the risk of human death from engagement in everyday activities. The unit is defined as a one-in-a-million chance of sudden death which enables medical doctors to more effectively compare intervention risks with the risks of other activities.

# One radian is equal to 180 divided by Pi.%0DWhat does a radian measure?

The symbol "rad" represents the mathematics S.I. unit radian. A radian is the intersection of two radii at a circle's center, where the angle's arc is equal to the length of the radius.

# What does a candela measure?

Candela is used in physics, and it expresses the luminous intensity in a certain direction from a source that emits monochromatic radiation with a frequency of 540 trillion hertz and a radiant intensity in that direction of 1/683 watt per steradian. But you probably knew that, right?

# What does the British stone unit measure?

In earlier times, the stone unit was a relative unit of measure used to weigh products. Today, the stone is used to measure large quantities (especially people and animals) and is equivalent to 14 pounds.

# One tonne equals one megagram. What does a tonne measure?

A tonne also equals a metric ton, and a hundredweight is equivalent to one twentieth of a ton. There are probably more "odd" measurements when it comes to weight and mass than anywhere else, because of their use in early commerce.

# What does a parsec measure?

One parsec is equal to approximately 3.26 light years. The parsec correlates to the range at which earth's orbit's mean radius subtends an angle of one second of arc.

# What does the "Big Mac index" measure?

The "Big Mac Index" contrasts the purchasing-power parity (PPP) of different countries based on the price of a similar item, like the "Big Mac." The PPP is then compared with actual currencies to gauge which currencies are overvalued or undervalued when compared with the U.S. dollar.

# Lake Tahoe, a freshwater lake on the border of California and Nevada, holds 39 trillion gallons of water. What does a gallon measure?

One gallon of liquid equals 3.79 liters. A liter measures liquid volume equal to approximately 1.75 pints, and a fluid ounce is one sixteenth of a U.S. pint (roughly 0.03 liter).

# What does a watt measure?

The watt is a S.I. unit of power that equals one joule per second. The watt correlates to an electric circuit's capacity, where the potential difference is one volt and the current is one ampere.

# Water freezes at 273.15 Kelvin, or zero degrees Celsius. What does Kelvin measure?

Kelvin equals 1/273.16 of the triple point water's thermodynamic temperature. The kelvin's magnitude equals that of degree centigrade (Celsius). Degree Celsius temperature is expressed as numerically equal to the temperature in kelvins reduced by 273.15.

# As a derived unit of measurement, one tesla equals one weber per square meter, correlating to 10 thousand gauss. What does a tesla measure?

The tesla is a derived unit of magnetic flux density, as well as magnetic field strength. The tesla more suitably measures strong magnets, and the gauss unit is used when measuring the strength of small magnets.

# Torque is most effectively produced if exertion is applied to a body perpendicularly. What does torque measure?

In physics, torque, also called the moment of force, changes the rotation rate of a body. Units that express torque are units of force multiplied by distance, such as pound-foot.

# A lightning bolt can carry anywhere between 15 and 350 coulombs, depending on its strength. What does a coulomb measure?

One coulomb equals one ampere multiplied by one second. The U.S. standard for one coulomb is the amount of electric charge transferred by a current of 1 ampere in 1 second, which is equivalent to 1 ampere-second.

# About HowStuffWorks Play

How much do you know about dinosaurs? What is an octane rating? And how do you use a proper noun? Lucky for you, HowStuffWorks Play is here to help. Our award-winning website offers reliable, easy-to-understand explanations about how the world works. From fun quizzes that bring joy to your day, to compelling photography and fascinating lists, HowStuffWorks Play offers something for everyone. Sometimes we explain how stuff works, other times, we ask you, but we’re always exploring in the name of fun! Because learning is fun, so stick with us!