Week 28 Reflection

This week we learned more about momentum and the transfer of energy.  We also used this new thing called gosoapbox that I thought was a great idea personally.  It was nice that throughout the class period you could answer questions about the lesson that the teacher puts up there.  I remember that we had to do a lab that involved using that website and looking things up online.  I think that it's a great idea. 

The entire week we were working on our Newton Cradles.  They were due on Thursday and we had to present them on Friday.  I think Devin and I's project worked pretty well.  We used ping pong balls that had needles stuck in them for eyelets for the string.  We cut out an old shoebox and used that for the frame.

We were told that the more rigid the object is, the more efficiently it transfers energy.  Even though ping pong balls are necessarily the most rigid objects, the still transferred the energy well.  We could do all the tricks that we were supposed to do.  We could drop 1, 2 and both ping pongs from both ends and have good results.

This week also involved the new soapbox website that we used.  The lab that we had to do with it involved us watching a video that Mr. Abud made I think explained what an impulse was and then he asked us a question at the end that we had to answer on twitter. (I'm taking that from memory, so I am probably wrong but that's what I thought it was talking about.)  I feel like we should use gosoapbox more often.

Week 27 Reflection

This week was all about momentum and energy transfer.  We have a project that is due on thursday that involves us making a Newtons Cradle to demonstrate what we are learning.  We also worked with the cars on the track to demonstrate how momentum is transferred to another object. 

Momentum is the movement after a force has been applied to an object.  So if I push a ball on the floor and nothing else pushes the ball afterward, its momentum is carrying it.  We also did work with "Momentum Blocks".  You take the velocity of the object in meters/seconds and put that one side of the block and then you take the mass in kilograms and put it on the other side and multiply them.  That is how you get your momentum in kg/meters/second.

This project that we are doing will be a good way to demonstrate transfer of momentum.  The more rigid the spheres are, the better the transfer.  I know that if you apply a force to a sphere (in this case gravity) it will hit the sphere next to it and start a transfer in momentum until it reaches the last sphere which isn't blocked by anything.  This is where it gets its motion from.

This week we also worked with the cars on the tracks to demonstrate what the transfer of momentum looked like with two things that could freely move and weren't blocked by anything.  We pushed one car into the other and observed what happened.  What happened was usually the car that was hit would take off and the other car would stop completely.  This is because the car that was hit took all of the energy and left the other car with nothing.

I think that this week was very succesful.  I believe that I got everything that was taught to me.  I'm pretty sure that I had some trouble with certain things on the exam, but I think I did fairly well, just by judging from taking the test.

Week 26 Reflection

This week we learned more about energy and how to calculate it.  We learned what joules, watts and power is.  We also used the results of an experiment that we did last week to get practice on finding joules, watts and power.  The experiment was where we had our class run up the stairs in groups and time themselves.  Using these measurements, we could find joules, watts and power.

We learned that joules are a measure of energy.  You find it by doing the equation massXgravityXheight.  To get watts you just divide that whole equation by the time.  Finally to get the horsepower, you multiply the watts by 0.0013.  We also learned that power is a rate of joules/time.

The experiment where we had people run up the stairs really helped me learn about joules, watts and horsepower.  Everyone timed how fast they could run up the stairs and we put everything into the equation to get joules.  It all started to make sense to me when everything had a place in its equation and we could get a number that represented the energy.

We also had an assesment this week.  It was about everything that we had learned about energy.  I was very thankful for the review the day before because there were still some things that I hadn't really understood up until then.  Things like the fact that power is a rate and not a unit and the difference between power and work.