Another Measure for Measure Trivia Quiz

Answer: metre

The yard is an Imperial measurement of distance. One yard equals exactly 0.9144 metre (as stated by law in the UK) and is divided into three feet, with each foot divided into twelve inches.

Imperial measurements for distance also include the chain (22 yards), the furlong (10 chains) and the (international) mile (8 furlongs).

Other distance units include the US mile, the Roman mile and the metric mile, where the Roman mile is the shortest (1,479 meters), followed by the metric mile (1,500 m), the international mile (1,609,344 m) and the US mile (1,609,347 m). To complicate things even further, sailors use the nautical mile (1,852 m).

Answer: kilogram

The pound, which is still in use, is part of the avoirdupois system. Here one pound is divided into 16 ounces, and each ounce is divided into 16 drachms. On the other hand, 14 pounds make up a stone, two stones equal one quarter, four quarters make up a hundredweight, and 20 hundredweights form a (UK) ton.
One (avoirdupois) pound is exactly the same as 0,453 592 370 kilogram.
In the USA and Canada the ton is defined as 2000 pounds, and thus a UK ton weighs more than a US ton. To add to the confusion, the metric ton is 1000 kilogram, and is more than a US ton but less than a UK ton.

Answer: second

It seems perfectly logical that hours and seconds both are units of time, but for use with the SI system, an hour has a practical inconvenience. All SI units are grouped by strict decimal multiples, but an hour does not equal 1,000 seconds: an hour is 60 minutes of 60 seconds each, so 3,600 seconds.
The SI seconds are grouped into kiloseconds, measurements equalling exactly 1,000 seconds or (in common language ) 16 minutes and 40 seconds.
Likewise a day (24 hours) or a week (7 days) are not used scientifically, but instead the megasecond (1,000,000 seconds) is used. If you try to make the calculation, a week is 604,800 seconds and thus the megasecond is a bit more than one and a half weeks.

Answer: kelvin

Most people measure temperature either in degrees Fahrenheit (USA) or in degrees Celsius (rest of the world). But these scales have one disadvantage: negative temperatures are possible. That's why scientists prefer the absolute temperature scale measured in kelvin.

The Fahrenheit scale has been calibrated so that (pure) ice melts at 32°F and (pure) water boils at 212°F, whereas the Celsius scale has the melting point at 0°C and the boiling point at 100°C. The Kelvin scale is based upon the Celsius scale, but adds the difference with the absolute zero temperature (-273,15°C). So 0 K is absolute zero, (pure) ice melts at 273,15 K, and water boils at 373,15 K.

There are a few other temperature scales, but their use is very limited.

Answer: candela

The candela is the SI unit for luminous intensity: the amount of light emitted in a certain direction. The first definition of a candela was the amount of light shed by a standard candle burning for one hour, but this was quite impractical: the slightest deviation from a "standard" candle would induce scientists in error.

Later on the candela was defined as (a 60th fraction of) the amount of light shed by melting 1 cm² of pure platinum - thus being independent of the testing equipment. A later refinement included the atmospheric pressure involved in this process, as this too could influence the outcome.

The Hefnerkerze was a similar unit, based not on the burning of a "standard" wax candle, but on the burning of a specific lamp burning amyl acetate.
Nowadays the Hefnerkerze is obsolete. For those who would still try an equation with Hefnerkerze, 1 Hefnerkerze equals 0,903 candela.
Other (obsolete) units of luminous intensity include the Violle, the Berliner Lichteinheit and the carcel. 

Answer: pascal

The pascal is the SI unit of pressure (force applied to a perpendicular surface). It is named after Blaise Pascal, a French mathematician who stated that the pressure exerted on a liquid, spreads in each direction.

The atmosphere is another unit of pressure, defined as the pressure exerted by 760 mm mercury at a temperature of 0°C. A pressure of one atmosphere (1 at) corresponds to 101,325 pascal.

Other units of pressure include the mm mercury and the bar.

Answer: joule

The SI unit for energy (force exerted over a certain distance) is the joule. But those who try to lose weight, are more interested in the number of calories (instead of joule) a certain food or drink brings to the body.
The calorie was defined as the amount of energy needed to increase the temperature of one gram of water by one degree Celsius. But as this amount slightly differs, depending on the initial temperature of the water, the calorie was not quite apt for scientific use. So enter the joule, defined as the energy transferred to an object when a force of one newton is applied to the object in order to move the object one meter.

To convert between these two units, one needs to know that one kilojoule corresponds with about 238,846 calorie , or that one kilocalorie equals 4,186,8 joule.

Answer: watt

As the non-SI unit clearly indicates, we have to do here with power : the amount of energy transfer per unit of time. The SI unit was named after the Scottish inventor James Watt, who ameliorated the steam engine to a useful tool.

Converting horsepower into watt is dependent on knowing which type of horsepower is applicable. Indeed, there are the mechanical horsepower (roughly 745,70 watt), the metric horsepower (roughly 735,50 watt), the electrical horsepower (exactly 746 watt), and the boiler horsepower (9812,5 watt).

Answer: litre

The gallon and the litre are units of volume, especially for liquid substances. In the SI system a litre is the volume contained in a cube of 1 dm³ (and if we're talking about pure water at 4°C, this should weigh exactly one kilogram).

Alas, there are different gallons. The US liquid gallon corresponds to 3,785 litre, while the Imperial gallon (used in the UK) contains 4,546 litre. And then we have the US dry gallon at 4,405 litre.

Furthermore, an imperial gallon (the greatest gallon) contains no less than 1,2 US liquid gallons.

Answer: hectare

These units are surface units. In the SI system, all surface units start from squares with equal sides: one square metre, one are (a square with a side of 10 m), one hectare (a square with a side of 100 m), one square kilometre.

In the Imperial unit system, things are quite different. The smallest surface unit in the Imperial system is the perch, calculated as the surface of a square with a side of one rod (where one rod equals 5,5 yards). But the next surface unit is a rood: the surface of a rectangle of one rod to one furlong. As one furlong equals 220 yards, a rood equals 40 perch. Next is an acre, being the surface of a rectangle of 1 furlong (220 yards) by 1 chain (22 yards). Finally we have the square mile, which is calculated as the surface of a square with a side of one mile (and one mile equals eight furlongs and 80 chains).

Converting acres to hectare or vice versa, you have to know that an international acre equals about 0,4047 hectare (or that one hectare corresponds to 2,471 acre).

The US acre is almost the same as the international acre: converting 1 US acre into international acre, results in 1,000 004 096 414 2 and so on.