Friday december 11 09

Friday we reviewed our homework (acceleration problems 3). The formula (with the exception of 8.a) for all of the problems was (sf-si)/t=a. the plug and chug follow.

1. (1.3cm/s-0cm/s)/100.75=0.01cm/s/s
   
2. (142km/h-0km/h)/0.0009=157,777.78km/h/h)
3. (287.6km/h-0km/h)/0.003h=95866.67
   
4. (om/s-32.7m/s)/143.7s=-0.23m/s/s
   
5. (41.5km/h-0kkm/h)/0.058=715.517km/h/h
   
6. (2.4m/s-7.9m/s)/-3.65m/s/s=1.51s
   
7. 9.8m/s/sx2.7s+0m/s=26.46m/s
8. A)s=d/t____40km/2.3h=17.39km/h

B) (17.39km/h-0km/h)/0.51h=34.1km/h/h
____________________________--_______
After that we did a little bit of work on our acceleration/deceleration lab by posting our results on a Google dock sent to us by Ms.D a week or so ago

Reminders!!!!!!!!!!!!!!!!!
QUIZ ON TUESDAY
LAB DUE THURSDAY

• Directions for lab on your data sheet
• Study for the quiz using moodle
• 50%+ on math
• Study with Ms.D Monday during lunch

The next scribe is Vance

Science Day!

Today is Science Day!
We had a 3-2-1 Pop! lab with paper rockets, a blog center, our laptop center and a ramp where we find the speed of a ball.
We'll keep you updated!
7th grade Science class!

On Tuesday we went over homework. Then we worked on our SCIENCE DAY projects. Some people are working on a Prezi, and some people on a ramp. My group worked on a spaceship project. We are going to measure the distance and time of the spaceship and then find out its speed!


Get Ready People! Science day is TOMORROW!!

The Next Scribe is.............. BRYCE!! You get to do SCIENCE DAY!!

On Thursday we had science day from 9 to 10. We had grade 1 and grade 2 coming in. They liked the ramp and the pop lab but the blog and prezis about speed and acceleration were a bit confusing. In the evning our parents come in. We showed them our blog and prezis. We also showes them our indiviual presentations.

Friday, December 4

Hello 7th graders! Last Friday, we reviewed our acceleration math sheets. This was split into two parts. The front was easier questions, while the back was harder questions, with conversions and finding velocity or time. One example of an "easy" question was "A three toed sloth is moving at a speed of 2m/min. It takes 30 min to increase its speed to 15m/min. What is the sloth's rate of acceleration." First you needed the formula, which was acceleration=final velocity-original velocity/time or a=sf-si/t. Next, the plug. a=15m/min-2m/min/30 min. The answer is 0.43 m/min. The "hard" questions on the back were similar, apart from the fact that you needed to convert or that you needed to find something apart from acceleration. Something that may help you is this triangle, similar to the one from before.

The next scribe is Noam.

Hello 7th graders! I want to start the post with a picture of us today (because we were outside in the freezing cold).











Today we started the class with the checking of our homework. The homework was a sheet of paper with acceleration problems. A type of an acceleration problem (and the answer) would look like this:

A cyclist began from a rest point at the top of the hill, then he starts downward and reaches the bottom with a speed of 50m/s in 20s. What was the acceleration of the cyclist? The problem would be solved like this:

Formula: acceleration = (Final velocity-Initial Velocity) /time

Plug: acceleration = (50m/s - 0m/s) / 20s

Chug: acceleration = 2.5 m/s/s or 2.5 mps 2(the two shows that "s" is squared)
or 2.5m/s 2(the two shows that "s" is squared)




After this we worked on a lab called Acceleration/Deceleration Testing". We first went outside into the main courtyard where we tested our capability of timing and the exactity of the timing. After several minutes of trying we were good enough. After this, we went outside and we arranged the whole class in a line at one meter intervals. There we each took our stopwatches and measured the exact time it took the ball to reach each one of us from the starting point. A very smart idea was using the gutter which had the sides tilted and that way the ball didn't follow another path. We measured 3 different kinds of balls, a ping pong ball, a tennis ball and a soccer ball. I, for example stayed at the four meters mark and collected the following data:

• ping pong ball: distance= 4 meters, time= 2.83 seconds, therefore speed= 1.41 mps
• tennis ball: distance= 4 meters, time=2.23 seconds, therefore speed=1.79 mps
• soccer ball: distance=4 meters, time =2.43 seconds, therefore speed=1.64 mps

For homework we reiceved the task of calculating the average speed of the time it took the three balls to reach us and also the speed of the three balls.





I also choose a movie about a peculiar Mr. Willard that might help you guys with the accleration problems. It's also kinda cool because it uses Ms. D's symbol for change (the triangle). These two movies were (in my opinion) clearl and understandable.

Before you comment look at the movies please

Next scribe is Alix

"http://www.youtube.com/watch?v=WFMdmMXS4Co"

My fabulous blog.

First this class Mrs D told us how to do a right conclusion.

You need Distance, time and speed in your conclusion.

Your errors must be something that affects your data.

Mention +, - or no correlation in your conclusion.



After that Mrs D lectured us on Acceleration.

Acceleration is not speeding up. It is the change in velocity. (speed increasing, decreasing and changing direction.)

Increasing acceleration is positive acceleration while deceleration is negative acceleration.

An example of changing direction in acceleration is circular motion. Examples of circular motion is a ferris wheel or a satellite.

A geosynconised satellite is a satellite that is always above one point on what it is rotating about.

Math in acceleration.

m/s/s is the unit for acceleration.

The Formula for speed is Final speed - Initial speed/Time

a sample calculation of working out acceleration is...

Formula: F - S / T = a Plug: 10m - 0m / 10s Chug: 1m/1s/1s You can not have m/s/m

The Next Scribe Poster is !?@# Cip