potential energy, kinetic energy, work, power... you've seen it before, I know... but -
What is the difference between a novice, and a master?
A novice and a master will both claim they know how to play the same song...
A novice and a master will both claim to know how to mix colors, or how to draw
The devil is in the details... even though you have seen this before, let's look at everything again, this time taking a little deeper look into it, and really pay attention to the details!
Other random information about mastery...
Next up? Potential Energy!
13.1-13.5 : See D2L for HW and examples:
Examples:13.5, 13.9, 13.26
HW:13.6, 13.27, 13.33 and
simulation work
Simulation practice:
Open up the ramp simulation:
http://phet.colorado.edu/en/simulation/ramp-forces-and-motion
Select the force graphs tab, and have a look around.
- Initial position, ramp angle, friction or no friction, and object can be chosen from the right hand ribbon.
- Force is set on the left hand side (just type in a number).
Problem #1:
Surface - ice - no friction!
Apply a force from -10 to 0, then pause the simulation, and reset the force to 0. In other words, push the crate on the horizontal ground to get it up to some velocity (call it V0, or V at position 0) then let go, and see how far up the slope it goes before gravity stops it, and brings it back down.
Goal - using :
T1+U1→2=T2Find the magnitude of the force applied from -10→0 that will just allow the crate to reach the top of the incline (at 10) before gravity wins and starts pulling it back down the hill.
Set up an excel sheet to calculate this for several different angles:
Fill in the above table, and then test it out! Try testing on the 1° incline first → (the crate is moving slower, and so it's easier to pause the simulation and reset the force to zero at x = 0. Try pausing the simulation just prior to the base of the ramp, so that the crate should stop moving just prior to the top wall)
- Graph the needed force as a function of angle.
- Graph the needed force as a function of horizontal distance it is pushed.
- Your choice - think about one other way you could analyze this problem, and create one more graph of your choice.
Problem #2:
Same as problem #1, only add friction, and choose something other than the crate to push up the incline. How does adding friction change all of the above graphs?
Problem #3.
Robot Moving company - play it a few times, use the snipping tool, and send your best score!
Justify your Strategy:
If this game allowed you to enter a numerical value for the initial force, what initial force would you use for each object? Is there a more energy efficient way to control it than from the initial force? How does your strategy change as a function of friction and weight of the object?
~~~~~~~~~~~~~~~
Weaning – or encouraging
Autonomous Learning
by Larry Spence
At 8:30 AM
she stood up in class. I wanted to
sit. She glared, shooting me with her
eyes. “I’m paying good money for this
class,” her thin hands shook. “My
parents are sacrificing. It’s your job
to just tell us what this book means.”
She waved a worn copy of Immanuel Kant’s essay, On the old saw: That May be true in Theory but it does not
Apply in Practice.
“what do you mean?”
“You will always have to take me with you. If you marry, I’ll be there. On your honeymoon, I’ll be there. You will need a special room to keep me in
your house. I misplace coffee cups and
scatter paper clips. I’ll need a desk
next to yours at work. A special seat
where I can work in your car…”
“Stop it!” she shouted.
“I don’t want to drag a professor through life.”
“Good,” I said. “Then
I can’t tell you what the book means.
Think of all the books, articles, policy papers, and memos that you will
have to read. If you don’t know how to
understand them, you will be lost as a citizen, a worker, and an
individual. So you can either figure out
what Kant means or you can adopt me for life.”
“I can do that, but it will burden the rest of your life.”
The class’s growing laughter filled the room as they imagined
living with a seriously uncool prof.
“But weren’t you paid to teach us?” asked a burly tight end.
“No, it is my job to see that you learn how to discover the
meaning yourself.”
“This class is weird,”
came a comment from the baseball cap section.
Students expectation that I could explain the world marred
every course I taught. Their
intellectual dependence was frightening.
On bad days, they were so docile and dependent I understood how good
storm troopers were made… But Oh, in the classroom the dependency is sticky and
thick. Students seem indifferent,
confused, and desirous only of getting this grade, that course, and eventually
the big ticket degree. The best strive
for that special relationship, “teacher’s pet.”
They work to say all those things that feed faculty egos. For many years, I saw little hope of
developing autonomous learners. Then I
made a discovery.
A group of my
students toured with a national champion drum and bugle corps. I went to see them perform. Their precision, quality, and panache
astounded me.I could not believe they were the same creatures that shuffled
through my courses. They worked twelve
hours a day on their musical skills, slept on gym floors, and were driven from
city to city without relief. They wre disciplined
adults.
I walked away with
words like “co-dependency” and “enabling” ringing in my ears. My best efforts taught students that to learn
was to follow instructions. They didn’t
need that or my careful explanations, or my crafted syllabi. They needed access to the world’s scholarship
and some tough coaching like they got in the bugle corps. And most of all they needed choice and
opportunities to pursue their own passions for inquiry and expression.
Maybe we smother
the best learning instincts of our students.
Seymour Papert writes, “ the scandal of education is that every time you
teach something, you deprive a child of the pleasure of discovery.” Maybe we should stop chewing and
pre-digesting the intellectual food we give our students. We nee not joke and enact an excitement we
wish they had. We need focus on
learning, and not the comfort of the
learners.
In earlier times,
people took the passion and energy of adolescents as signs of maturity. They weaned them on responsibilities. The impetuous George Washington was surveying
frontier lands by the age of sixteen. By
21, with only a few months of formal education, he could ford rivers, chart
mountains, charm legislators, and lead
troops. Lord Fairfax wrote his mother
that he was, “a man who will go to school all his life.” Washington
