Part 14
Let's learn the secrets of stationery!
in a space station, where there's no gravity.
Which of these can write in space?
Oh dear, that's not right.
Hey, what gives? No ink is coming out!
I guess ballpoint pens don't work in space...
HintThere's a certain force that works on Earth but disappears in space.
Correct!
When pencils rub against paper, they transfer graphite even without gravity.
By the way, markers use capillary action to carry ink to the tip,
so they also work without gravity!
Correct!
The ink in a marker travels to the tip by capillary action,
so it can write even without gravity.
By the way, pencils transfer graphite when rubbed against paper,
so they also work without gravity!
without needing to press too hard?
Which pencil can write clearly without
needing to apply much pressure to the tip?
Compare the different pencil grades and electron microscope images.
Oh dear, that's not right.
Hmm, this pencil has a hard lead and doesn't write well with weak pressure.
HintCheck the 17 pencil grades again.
Correct!
6B pencils contain the largest amount of graphite among the 17 pencil grades.
This results in a soft lead that writes dark and clear text even with minimal pressure!
