Some notes

More mass, harder to accelerate, longer period
Amplitude/drop height no effect
Spring constant t= c1/square root k
Is the y intercept neglible for mass
2 high r squared values suggesting linear and power
Power fit was agreed on
T=c square root of mass

T =2pi square root of m over k
Simple harmonic motion

Mass affects spring oscillation

Pendulum not affected by mass
2pi square root of l over get

This is all a little confusing to me, especially since I'm a little unfamiliar with simple harmonic motion. I'm also really bad at the graphs that were on the first page of the quiz, I need to learn how to do that.

Centripetal force

The centripetal force is directed on an object in a circular motion towards the center of the circle. We were given a helpful packet with equations and explanations. On the quiz, I did pretty well. I got all the momentum questions right and on the centripetal part, for acceleration I did 4pi^2/t which it should've been t^2. I guess what sort of confuses me is where the force comes from. Like if you think of a runner on the track, the friction is the centripetal force. Its a little confusing that the friction causes the runner to go inwards, but if you think about it, the runners natural tendency would be to go straight. If you look at the diagram above, the runner would follow the path of inertia, but due to friction it doesnt. But this is still confusing I'll be honest. In the picture above is the force coming from the string or the person?
Im decent with calculations and what not because the equations are given. So if the question is asking for velocity, you plug the known information in one of the given equations, but its understanding the equations, and breaking them apart to figure out where they're derived from is what is difficult for me. I feel like I have a general understanding of centripetal force, but I need to work towards a deeper one.

The flying pig, here is a picture of our work. We were trying to find the force on the string and this involved many different equations such as the pythagoreum theorum and the force equations. We had to find the force on the string, so as you see we drew a force diagram. We decided to find the earth force (mass) and the centripetal force, and then with our vector knowledge, we could use the pythagoreum theorum to find the hypotneuse aka the force on the string.

Reflecting on Reflecting!!!/Momentum test corrections

YIKES! My last blog was in January. I feel like since february is a short month, and we've had a break in between, I've been thrown off my blog schedule. Excuses, excuses. Honestly, I think the reason I haven't been blogging is because I put off blogs when I don't understand something. I know this defeats the purpose of reflecting, because if I don't completely understand something I could easily say "this is hard for me to grasp because..." but for some reason I just put it off. I guess I just like to know what I'm talking about, and also sometimes I just don't know what to say in a blog if i'm not understanding the class material. Basically, my last blog was on energy...so that means I skipped over momentum.

Momentum
Momentum was interesting because I though I understood it...and then the test came and :((((. Honestly, I seriously understood all the problems we've white boarded in class so when I didnt do too hot on the test I was slightly surprised because i understand P=MV. Okay so on that test, I didnt even really attempt the last question because the graph confused me, but now I totally get it and i'm like REALLY.
So the graph is a FORCE vs Time graph, and I didnt process that FORCE MULTIPLIED BY CHANGE IN TIME IS IMPULSE. honestly like duh.
So now the problem is straight forward.
A. Impulse of the rocket engine?
F=20 T=.5
(20)(.5)=10
Need to account for the triangle
10(.5)
Answer: 5kgm/s

B. determine rockets burnout velocity
5=.3v
divide by .3
vf=16.7 m/s

C. Determine acceleration
a=v/t
16.7/.5
a=33.3 m/s/s


ON NUMBER 17 I CONVERTED WRONG. honestly the dumbest reason to lose points for. I ALWASY CONVERT CM TO KM. I think its a habit of mine just to turn everything into kilo, but centimeters goes to meters. I literally messed this up on the centripetal quiz the other day too, same exact mistake.

19. I didn't account for direction, and this is important with momentum. Other than that my work is correct

Ratios are too much to reflect on the blog here because I got basically all those wrong. But I went over these with my table and I am aware of what I did right and what was wrong, and I have notes and everything on that. Overall on this test, the ratios were the only thing I feel like I was weak on, but I think since then my understanding has improved.

LOL charts

Another fairly simple topic is LOL charts. We are very familiar with these because we did these freshman year and then in chem again last year. So I didn't really struggle with these. Basically you identify what's in the system. Then you identify what energies are present at that moment of time. For instance, in number one in position the cart is not moving. It has elastic energy from the spring, and then in position b the cart is both in the air and moving. This means it has both elastic and kinetic energy. Basically how I think of it. Is moving?? If yes then it has kinetic. Is it off the ground??? If yes, then it has gravitational. Is there a spring involved in that moment??? If yes, then it has elastic. #2 on the paper is a little tricky. The idea of Work is introduced. The problem looks identical, except it says to exclude the spring from the system. Since there is no spring in the system, you can't account for the elastic. So how did you get from point a to point b?? The energy had to come from someone. You call this work. And as you see, the last problem involves dissipated because you need to account for friction. Note on those charts, dissipated is not on the first LOL chart at position A but only the one at position b. The energy could only go towards the friction if it is moving, therefore it would not make sense to have dissipated on the beginning. Overall this was just a big review from freshman year, so I found this fairly easy.

Energy pie charts

The question is on the paper, the answers are on the white board. These problems were fairly easy. I didn't struggle much with them. The one thing that was introduced to me was dissipated energy. Before this, I feel like we would neglect friction and air resistance, so often times I forget to include that. Dissipated energy is a new concept, that I didn't know about before. It's basically when the energy into the system goes into something else such as noise, friction, air etc. For these pie charts, they are good representations to see what energies are increasing and what energies are decreasing. For instance in number five, as the you is going higher, there is more gravitational taking away from the elastic while the kinetic remains the same. I think these were easy, and a nice way to introduce a new unit