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adamp
2005-Jan-23, 05:36 PM
Guys maybe you can help me on this-
The other day I was in Fluid Power class, and the instructor mentioned something which i did not agree with. He said that there is a difference between inches squared and square inches, is this correct? He said that, for example, 4 inches squared would actually be 16 square inches. I thought that 4 square inches and 4 inches^2 were the exact same thing. So tell me guys, am I mistaken?

Moose
2005-Jan-23, 05:41 PM
Guys maybe you can help me on this-
The other day I was in Fluid Power class, and the instructor mentioned something which i did not agree with. He said that there is a difference between inches squared and square inches, is this correct? He said that, for example, 4 inches squared would actually be 16 square inches. I thought that 4 square inches and 4 inches^2 were the exact same thing. So tell me guys, am I mistaken?

Am I alone in thinking this thread has the potential of rivalling the 1 = .9999~ thread?

For what it's worth:

4 inches squared = (4 * 1)^2 = 16 square inches.
4 square inches = 4 * (1^2) = 4 square inches.

Your instructor is right. It's all about the implied parentheses.

Mistermystery
2005-Jan-23, 06:09 PM
The correct awnser is that you guys should use the metric system. Problem solved.

Maksutov
2005-Jan-23, 06:15 PM
The correct awnser is that you guys should use the metric system. Problem solved.
A square's a square no matter where!

Wilkommen!

("awnser": is that a Katherine Hepburn impression? :D )

Mistermystery
2005-Jan-23, 06:20 PM
The correct awnser is that you guys should use the metric system. Problem solved.
A square's a square no matter where! Oh I'm only joking with this guy.


Wilkommen!That's German, but nice try, and thanks none the less :)


("awnser": is that a Katherine Hepburn impression? :D ) I could tell you, but then I'd have to kill you.

kucharek
2005-Jan-23, 06:26 PM
The correct awnser is that you guys should use the metric system. Problem solved.

It's a language problem, not a unit problem.

In German, we we say "9 Quadratzentimeter", which means 9cm^2, which describes the area of a square 3cm x 3cm or a triangle with a base of 6cm and a height of 3cm or...
When we say "3 Zentimeter im Quadrat", it means literally a square with 3cm x 3cm edges, it's more a description of the area's shape than a measurement of the area.

I think, the semantics of "4 square inches" and "4 inches squared" are similar.

Harald

Nicolas
2005-Jan-23, 06:48 PM
In Dutch there is only the "16 vierkante centimeter" expression, which means 15 cm². The only other option in speaking language is "4 bij 4 cm" which means "4 by 4 cm" :). But no "4 cm squared" equivalent, and I'm glad for that because I find it confusing.

kucharek
2005-Jan-23, 07:01 PM
In Dutch there is only the "16 vierkante centimeter" expression, which means 15 cm².

(emphasis mine)


The only other option in speaking language is "4 bij 4 cm" which means "4 by 4 cm" :).
But no "4 cm squared" equivalent, and I'm glad for that because I find it confusing.

Yeah. You already got without that. :P

Aren't you in aerospace industry? Maybe I should give a second thought on the A380... :evil:

W.F. Tomba
2005-Jan-23, 07:13 PM
Couldn't "4 inches squared" sometimes just mean 16 inches? For example, if I you travel 4 inches, and I travel the same distance squared, I've traveled 16 inches.

I think "x units squared" is an ambiguous construction that you should simply avoid.

Mistermystery
2005-Jan-23, 07:20 PM
Apperently german-boy here can't understand a joke... Or I can't tell it...


Probably the latter.

Ut
2005-Jan-23, 08:25 PM
Couldn't "4 inches squared" sometimes just mean 16 inches? For example, if I you travel 4 inches, and I travel the same distance squared, I've traveled 16 inches.

I think "x units squared" is an ambiguous construction that you should simply avoid.

No, you have to square the units, too. "x units squared" => (x units)^2 = x^2 units^2. What you're describing is 4 inches + 4 inches + 4 inches + 4 inches = 4 x 4 inches = 4^2 inches = 4 squared inches.

Enzp
2005-Jan-23, 09:19 PM
To really pick nits, I don't think 4 inches squared is a good phrase anyway.

You can have four square inches, which means four square spaces each one inch on a side or the eqivalent - for example a square with 2" sides. This county covers 100 square miles.

The othre option would be 4 inches square. Not 4 inches squared. 4 inches square meaning a square 4 inches on a side. 16 square inches. This county is 10 miles square.

4 inches squared sounds like an improper construct combining two forms. Like mixing metaphors in math. 4 inches squared then has no real meaning, unless you accord it some in your context. But having said that, if I read it I would assume you meant 4 inches on a side - 16 square inches.

But inches square and square inches definitely are different.

I may be wrong on the following example, but I have similar trouble with advertising copy saying "save up to 50% off." I think they should either say "save up to 50%" or "50% off" but not use both contructs in the same sentence. Almost like the "3AM in the morning" thing. If that makes any sense.

Maddad
2005-Jan-23, 11:25 PM
The correct awnser is that you guys should use the metric system. Problem solved.A square's a square no matter where!I side with the professor on this one. Four square inches means four of them. Four inches squared means 16.

bluebonics
2006-Oct-24, 05:23 PM
I see a lot of people having problems with this. here goes... four square inches = 4in^2 four inches square = 4in^2 but four squarED in = 4^2in = 16in. (for the person who mentioned the metric system) It's the same as cubic centimeters and centimeters cubed, both = cm^3 but four cubed centimeters = 4^3 cm = 64cm. I hope this clarifies things.

bluebonics
2006-Oct-24, 05:28 PM
where i wrote four inches square i meant four inches squared = 4in^2 ... so just for a repeat... four square inches = 4in^2 four inches squared = 4in^2 but four squarED inches = 4^2 in = 16in. ... in^2 is its own unit and can be read as square inches or inches squared just as cm^3 is its own unit and can be read as cubic centimeters or centimeters cubed... but if the number is directly followed by the squared or the cubed (notice the ED on the squared, this is where a lot of the confusion comes in) then the exponential process is applied to the number and is not a part of the unit of measurement.

lti
2006-Oct-24, 10:46 PM
argh! another incredibly simple concept somehow becomes confusing to someone.

are u squaring the number? or the unit? thats what u have to ask yourself.

See bluebonics post.

01101001
2006-Oct-24, 11:08 PM
He said that, for example, 4 inches squared would actually be 16 square inches.

Let's ask Mr. Google!

Query: 4 inches squared in square inches
Reply: 4 (inches squared) = 4 square inches

Query: 4 square inches in inches squared
Reply: 4 (square inches) = 4 inches squared

While your instructor may correctly recall what he was taught in the olden days, when Google finally achieves total world domination, there will be no difference.

Wait. How did he punctuate his statement? He isn't one of those people who thinks the parentheses are silent, is he?

Query: (4 inches) squared in square inches
Reply: (4 inches) squared = 16 square inches

Query: (4 squared) inches in inches
Reply: (4 squared) * inches = 16 inches

worzel
2006-Oct-24, 11:25 PM
After reading this thread the word "squared" sounds really silly to me now, like it's a new made up word like "splugged" or something. Does that happen to anyone else?

I think he has a point. When someone says 4 squared (cringe) inches they could mean 4 x 1 inch squared (ouch). But then 4 inches squared (argh) could mean an inch squared (grr) but 4 of them, too. Which way round did the instructor have it?

hhEb09'1
2006-Oct-25, 12:03 AM
After reading this thread the word "squared" sounds really silly to me now, like it's a new made up word like "splugged" or something. Does that happen to anyone else?

I think he has a point. When someone says 4 squared (cringe) inches they could mean 4 x 1 inch squared (ouch). But then 4 inches squared (argh) could mean an inch squared (grr) but 4 of them, too. Which way round did the instructor have it?The OP (a couple years ago) said "4 square inches" not "4 squared inches", otherwise I think that was his point.

worzel
2006-Oct-25, 01:07 AM
Thanks hhEb.

Gillianren
2006-Oct-25, 05:23 AM
After reading this thread the word "squared" sounds really silly to me now, like it's a new made up word like "splugged" or something. Does that happen to anyone else?

No, I'm totally there. The word has lost all meaning. Fortunately, it's one I don't use very often anyway.

clop
2006-Oct-25, 05:29 AM
Guys maybe you can help me on this-
The other day I was in Fluid Power class, and the instructor mentioned something which i did not agree with. He said that there is a difference between inches squared and square inches, is this correct? He said that, for example, 4 inches squared would actually be 16 square inches. I thought that 4 square inches and 4 inches^2 were the exact same thing. So tell me guys, am I mistaken?

I'm not so incredibly old and I was taught very specifically that there is an important distinction between 4 square inches and 4 inches squared. The first is an area of 4 square inches and the second is not. For many years, if I used the wrong term in my answers, they would be marked as wrong.

clop

Mellow
2006-Oct-25, 09:05 AM
I'm not so incredibly old and I was taught very specifically that there is an important distinction between 4 square inches and 4 inches squared. The first is an area of 4 square inches and the second is not. For many years, if I used the wrong term in my answers, they would be marked as wrong.

clop

Clop, I was going to write the identical post, I'll even admit I've just hit 40 years old, but was always made aware of the distinction in junior school classes. I had the fun of being schooled as the UKI moved (partially) from the imperial to metric systems...

I now think of cold tempuratures in degrees C "ooh it's cold out, yup -2 I think" but warm temperatures in Farenheit... "What a scorcher, must be 90 degrees!"

I measure distances in miles mainly, but Kliks to an extent, my height is 6 foot 2 inches, but my weight is 96 kilos I'll lend you half a kilo of sugar but only if you buy me a pint of beer and if I can borrow ten pounds from you today, I'll give you back fifteen Euros next week when we are in Paris......

yup, I'm confused.

clop
2006-Oct-25, 09:07 AM
Heh heh, I'm 12 stone 3.

clop :)

worzel
2006-Oct-25, 09:37 AM
Being educated in both the UK and NZ I confuse metric and imperial measurements terribly (lucky I don't work for NASA :) )

Walks and walking speeds are measured in miles and miles per hour but other modes of transport use kilometres.

Smaller distances are measured in metres or centimetres except for people's heights which are measured in feet and inches, and room dimensions which are measured in yards.

Food is bought by the gram or kilogram (and grocers who insist on sticking to pounds really annoy me cos I don't know how much a pound of asparagus is) but people's weights are in stones and pounds (I don't have a clue how many kilograms people are).

If I had an interest in horses I'm not sure if their heights would be measured in hands or centimetres.

Gillianren
2006-Oct-25, 09:53 AM
Smaller distances are measured in metres or centimetres except for people's heights which are measured in feet and inches, and room dimensions which are measured in yards.

Here, it's in square feet, which is, yes, different than feet squared. If they were the same thing, my apartment would be a lot bigger than they're saying it is. (Or else quite a lot of other things I've measured would be a lot smaller!)

worzel
2006-Oct-25, 10:29 AM
Here, it's in square feet, which is, yes, different than feet squared. If they were the same thing, my apartment would be a lot bigger than they're saying it is. (Or else quite a lot of other things I've measured would be a lot smaller!)
Here in central London I think squre inches would be more approriate :)

LayMan
2006-Oct-25, 01:48 PM
argh! another incredibly simple concept somehow becomes confusing to someone.

Tell me about it! Tsss, some people... :D :D

Couldn't we just round the whole thing to, say, a neat 10?

gwiz
2006-Oct-25, 02:57 PM
I'm with the instructor.

In much the same way, in countries which use a more rational system of units, there is a difference between four square metres and a four metre square.