Common Misconceptions Taught By School Teachers (Revived Topic)

[Knowledge_Seeker]

Today in my world studies class (im a freshman in high school), my teacher was talking about Columbus. And then she talked about how the world wanted to learn more and discover new things.

This is what she said:

"What did most of the people at the time believe about the earth?"

Class Says [not me]: the earth is flat

She says: "Yes. Most of the people at the time belived that the earth was flat. And this makes sense too, becuase if you looked out into the ocean you would see nothing up to the horizon which would make you think there were sea monsters out there and you would fall off the earth."

And I wanted to challenge my teacher, but she is the type who would argue back, and although i know i would win if i had internet access at the time, she would still say something like, "but most people belived that."

and i would say that most people belived that only because they werent educated about it then, because besides people like peasants, everyone would know.

http://en.wikipedia.org/wiki/Christopher_columbus -second section

[VTBoy]

That the primary colors are Red, Blue, and Yellow.

[Tobin Dax]

Correct her. At the very least, you tried. At most, you'll get her to teach better.

Even though most people may have thought that the earth was flat,
what does that have to do with Colombus? He knew better. It's obvious to any sailor that the Earth is round (ships come over the horizon), and scholars had known it for millenia. He just had a bunch of bad assumptions. They teach that the search for the northwest passage was driven by trade, would it really be so bad to teach that Colombus' trip was, too?

[clop]

Erastothenes measured the circumference of the earth in around 200 BC.

That was 1650 years before Columbus was born.

clop

[Knowledge_Seeker]

That the primary colors are Red, Blue, and Yellow.


I also know this information is false, but what are the actual primary colors, i tried searching for it but i couldnt find it

[Knowledge_Seeker]

Correct her. At the very least, you tried. At most, you'll get her to teach better.




Yeah, i realized that after she finished talking about it in class. i kind of regret that i didnt say anything, but i guess i didnt want everyone in the class to feel that what i was saying seemed false to what they already knew.

[Jeff Root]

It's good that Knowledge_Seeker re-created the thread to present
first-hand reporting of fresh info. No problem with that!

I do want to point out, though, that we have been over both of
the topics brought up so far: Popular knowledge of the shape of
the world in Columbus's time, and primary colors.

As primary colors are an interest of mine, I'll point out again that
there is nothing wrong with saying that red, blue, and yellow are
primary colors. They are. Red, blue and yellow are primary colors
of opaque pigments, as in most paints, such as tempera paints.
Yellow, cyan, and magenta are primary colors of transparent
pigments, as in watercolor paints and color printing inks. Red,
green, and blue are primary colors of light, as in TVs and
computer monitors.

-- Jeff, in Minneapolis

[VTBoy]

It's good that Knowledge_Seeker re-created the thread to present
first-hand reporting of fresh info. No problem with that!

I do want to point out, though, that we have been over both of
the topics brought up so far: Popular knowledge of the shape of
the world in Columbus's time, and primary colors.

As primary colors are an interest of mine, I'll point out again that
there is nothing wrong with saying that red, blue, and yellow are
primary colors. They are. Red, blue and yellow are primary colors
of opaque pigments, as in most paints, such as tempera paints.
Yellow, cyan, and magenta are primary colors of transparent
pigments, as in watercolor paints and color printing inks. Red,
green, and blue are primary colors of light, as in TVs and
computer monitors.


-- Jeff, in Minneapolis

WRONG. There is no such thing as primary colors of opaque pigments.

It is impossible to make cyan from any red, blue, and yellow paint. You can make blue though from any paint, if you have cyan, magenta, and yellow.

The primary additive colors are Red, Blue, and Green.

The primary subtractive colors are Cyan, Magenta, and Yellow.

[Dragon Star]

Erastothenes measured the circumference of the earth in around 200 BC.

That was 1650 years before Columbus was born.

clop

Ain't that a...

:lol:

[Jeff Root]

There is no such thing as primary colors of opaque pigments.

It is impossible to make cyan from any red, blue, and yellow
paint. You can make blue though from any paint, if you have
cyan, magenta, and yellow.
It is possible to make dark cyan from a mix of blue and yellow
opaque pigments. You are right that is not possible to make a
light or bright cyan from red, blue and yellow opaque pigments.

It really isn't possible to make any decent blue from cyan,
magenta, and yellow opaque pigments.

However, you can get a much wider range of colors if you add
white to the list of opaque pigments, nomatter what triad you
use for primaries.

-- Jeff, in Minneapolis

[Gemini]

I had a sub in 2nd grade that tried to teach us geocentricism :D :(

[VTBoy]

It is possible to make dark cyan from a mix of blue and yellow
opaque pigments. You are right that is not possible to make a
light or bright cyan from red, blue and yellow opaque pigments.

It really isn't possible to make any decent blue from cyan,
magenta, and yellow opaque pigments.

However, you can get a much wider range of colors if you add
white to the list of opaque pigments, nomatter what triad you
use for primaries.

-- Jeff, in Minneapolis

"Dark Cyan" isn't the same as true Cyan. When I took art in college we used 7 colors of acrylic paint: Cyan, Magenta, Blue, Red, Yellow, White, and Black. According to my professor this was the best way to get a good range of possible colors.

[Jeff Root]

"Dark Cyan" isn't the same as true Cyan. When I took art in
college we used 7 colors of acrylic paint: Cyan, Magenta, Blue,
Red, Yellow, White, and Black. According to my professor this
was the best way to get a good range of possible colors.
The more different pigments you use, the wider the gamut
you can reproduce.

Can you say which actual pigments you used? I have cobalt
blue, cadmium red, cadmium yellow, titanium white, and mars
black. Those are all very conventional and I imagine you have
the same, even though hundreds are available. What about
the cyan and magenta pigments?

-- Jeff, in Minneapolis

[Ronald Brak]

Before Columbus most people (Europeans?) thought the world was flat - Wrong.

Before Columbus most people (Europeans?) thought the world was round - Wrong.

Most people did not "think" about this subject at all.

[jfribrg]

Erastothenes measured the circumference of the earth in around 200 BC.

That was 1650 years before Columbus was born.

clop

My understanding is that someone in the early middle ages calculated an "improved" circumference of the Earth. Instead of the more accurate ancient measurement, the "better" measurement was 14000 miles. With the information about Marco Polo's travels, the ocean was therefore only 4000 to 5000 miles wide. If Columbus had thought that the distance to the far east was 11,000 miles, and no knowledge of a continent in between, he would never had tried.

[BigDon]

Why do people insist on bickering about what is essentialy the differences between light and pigment? I've got a brother who paints. I've had to hear ad nauseum.

[worzel]

Because people forget that we have red, green and blue cones in our eyes. That's what defines the additive primary colours (and indirectly, the subtractive primary colours). If we had cones sensitive to different frequencies (or cones that reported actual frequencies to our brains) then neither our monitors nor our printing processes would yeild anything like true colour.

[Tobin Dax]

I had a sub in 2nd grade that tried to teach us geocentricism :D :(

I'm teaching Geocentrism tomorrow. Just for a bit, though, since I need to cover Copernicus, Tycho, and Kepler, too. :D

[hhEb09'1]

Most people did not "think" about this subject at all.Cite? :)

[worzel]

Cite? :)
Maybe he meant most people here.