9/7 qod

What is the advantage to using unit vectors instead of the polar form?

-- ch

9/06 Han

Today, September 6th, the first thing we did was turn our Vector Addition Partner Check that was either completed in class on Friday, or done for homework over the weekend. We then proceeded to check our Vector Addition 1 homework assigned to the class over our long weekend and asked questions if we encountered any problems. As we continued to check the homework, Coat-Haan passed out another partner worksheet, the homework, as well as copy of the unit circle. After we had all finished checking our homework, we passed back the answer keys and told to get out a piece of paper. We took copious notes, learning a new method to solving vectors not drawn at 90 degrees. Our notes included the steps to solving these vectors, what quadrant the vector was in and what action to perform on that angle (nothing, add 180 degrees, or add 360 degrees). As this great class continued, so did the wonderful notes. Coats-Haan then taught the class of the ROXY chart method, which used the other two vectors and their sine and cosine functions, in order to be able to use the Pythagorean Theorem and inverse tangent to find the direction of the third vector. We did an example of how to use the ROXY chart method together as a class and the teacher explained how to solve the problem. We went on to talk about the unit circle, with the copy we received as we were checking our homework. Coat-Haan explained how the unit circle was set up and how to locate the points of different angles (we need to know this chart for the test). Taking the partner worksheet also handed out with the unit circle and homework, we got together with our partners and worked on the problems. After we had completed each problem, we compared our answers with the answers posted on the board. For most of the class, the worksheet was not completely finished, but don't worry, unlike the other partner worksheet, this one did not have to be complete for homework. Instead, if you had completed all the problems up through number 4, you could turn it in. Though the whole class dreaded it, the bell finally rang, signally the end to another memorable Physics class. We all grabbed our homework, which was another Vector Addition Worksheet, and regretfully exited through the door into the crowded hall.

QOD Answer:

ROXY allows us to create a right triangle through the sine and cosine functions. This allows us to then use the Pythagorean Theorem and inverse tangent to find the last vector.

9/6 qod

How is ROXY a combination of adding collinear vectors and adding right angle vectors?

-- ch

9/02 Gaitan

Today, on Friday September 2^nd, we had one assignment due, and it was the Measuring Vectors Lab.  Each group completed the Vector Addition POGIL as well as the peer evaluation paper about the POGIL.  A specific member in each group turned in the POGIL, and we all turned in the peer evaluation paper along with it.  For the groups that did not finish the Pair Check, it was assigned for homework, along with the Vector Addition I Homework.  We were supposed to have grasped the point on how to successfully measure the lengths of vectors, the directions of them, as well as plotting the lengths and directions of the vectors.  Learning how to perform each task in our group was also something important.  We also need to know what a resultant vector is and how to plot it and spot it.  Since we ran out of time to learn how Bernoulli’s principle applies to the kites that we had made, we went over that.  When you add two vectors that form a right angle with each other, you have to use the Pythagorean Theorem and also use tangent in order to figure out the length and direction of the resultant vector.

9/2 qod

How do you add two vectors that form a right angle when drawn head to tail?

 

--ch

9/1 Clyde

Today we turned in our What is a Radian? lab that we had on page 5 of our lab manuals, also returning any protractors we borrowed. Once we’d done that, everyone had to set up their books and binders in a line in the middle of the table so that nobody could see what was going on on the other side of the table. We then received the mysterious ‘Ye Ole Treasure Map’, with a picture of a pirate ship in one corner and a treasure chest in the other. Half of each table received blank maps with just these, while the other half had complete maps, which showed all of the dangers awaiting us in the sea, and the only safe path to get to the treasure! The students with complete maps then used rulers and protractors to attempt to lead the students with blank maps to the treasure chest at the end without being blown to smithereens by running into a mine, being eaten by running into a shark, or peeking at the answers. After completing this dangerous task, luckily with no severe injuries or deaths (because no one is allowed to die in physics), Brian’s team was successfully able to reach the end of the puzzle before the rest of the class and received the priceless booty inside... candy.

As those two ate their newly-won Dum Dums, the class transitioned into a new activity, a POGIL. We were assigned specific roles to play as we worked on the POGIL packet about vectors. Most groups got through the first page before we wrapped up class and left.

In the way of homework, we were assigned Page 7 of our lab manuals,  Measuring Vectors. While the page in the manual gives an example for what we should use as a scale, it’s not advised that you use said scale, unless you’d like to tape together 9 meters’ worth of paper just to finish number four. 1/10mm = 1km would be the recommended scale. You know, unless you wanted to do that 9 meters of paper thing.

QOD:

The information needed to accurately describe a vector would be the angle, the length of the line (or magnitude), and the reference line. This last bit was what got most of us on Ye Ole Treasure Map, as several of us were measuring on the opposite side of the reference line as those guiding us, and ending up going in all the wrong directions. However, having all three pieces of information would allow someone to successfully replicate a vector.

9/1 qod

What information do you need to accurately describe a vector?

 

-- ch