10/26 Chem Update and homework due 11/2

Hi folks,

We are starting a block on heat and temperature.  Since heat is the movement of energy, I gave the students a brief overview of the concept of energy.  So....what is energy?  Well, that's not that easy of a question to answer.  Today's class tried to define it and it's not simple. 

Energy is defined in the physics books as being able to do work.  Uh huh, great...so what's work?

Work is the exertion of force over a distance.    So, work is when something gets pushed or pulled over a distance.  Mathematically it's Work = Force x Distance.   If I was to lift an apple up a flight of stairs, I would be doing work.  However, if I where to push against a wall with all my might, and if the wall never moved, I would be doing no work.  There was no distance moved.  Also, if instead of lifting that apple up a flight of stairs, I only moved it across the table, I also did no work.  There was distance but there was really no force (a slight bit of force overcoming friction but very little).  Another way to look at this, is to say that work is done if energy is changed.  By pushing on the non-moving wall, no energy is changed in the wall.  By moving the apple across the table, no energy is changed for the apple.  If I lift the apple up a flight of stairs however, the apple now has more potential energy then it had when it started.  The apple's energy has changed so work has been done.  (We'll define potential energy more next week.)

If we wish to talk about energy further we need to have a unit of measurement.  For energy, a couple of units are the Joule or the Calorie.  A Joule is the energy needed to lift one Newton one meter.   "Arrghh, Jim, there's another new word!!! What in the world is a Newton?!" Sorry, your right.  Ok, a Newton is a unit of force.  One Newton is about the amount of force it takes to lift an apple.  So, if you lifted an apple one meter (about 3 feet) into the air you would have exerted one Joule of energy to do it.  The calorie is generally used to talk about heat energy and you're familiar with due to food and exercise.

Homework due 11/2

We also worked a bit with creating and working with formulas today.  For homework next week, I'd like the students to complete the enclosed worksheet on converting english to mathese.

Never Stop Wondering

"Science Jim"  Mueller

(919) 929-9791

A Fun Approach to Serious Physics!

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Re: .pdf for homework

Hi folks,

Taegan pointed out that there is something wrong with the answers for the last few questions.  Here are the correct answers.

26 should be =  

27 should be >

28 should be <

29 should be =.

Sorry about that.  Good catch Taegan!

Never Stop Wondering

"Science Jim"  Mueller

(919) 929-9791

A Fun Approach to Serious Physics!

Sciencejim

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On Oct 24, 2012, at 3:22 PM, M Mullane wrote:

Jim, In the homework you said that number 27 and 28 were equal. I was just looking at it with a metric prefixes chart, like the one that I have in my notes, in my mom's old chemistry textbook and I don't understand how these can be equal. Just using the chart that I copied down it might look like they are equal but there is a measurement in between none and centi so it doesn't look like it is possible. The same same thing goes for number 28. I don't know if I just don't understand it or if there is an error on the homework answers. Can you please clarify? Peace, Taegan   --- On Mon, 10/22/12, Jim Mueller <jim@bitesizephysics.com> wrote: From: Jim Mueller <jim@bitesizephysics.com> Subject: .pdf for homework To: Date: Monday, October 22, 2012, 6:52 PM Hi folks, Sorry about that.  Apparently this didn't attach the first time.  Let's try that again. Never Stop Wondering "Science Jim"  Mueller (919) 929-9791 A Fun Approach to Serious Physics! Sciencejim Join my Facebook page! Facebook | Science Jim

.pdf for homework

Hi folks,

Sorry about that.  Apparently this didn't attach the first time.  Let's try that again.

10/19 Chemistry update and homework due 10/26

Hi folks,

Today we spent time on basic science math stuff.  We went over the rules for significant figures.  We also went over some basic english to metric measurement conversions.  Briefly covered exponential notation and lastly, did some metric conversions.  

Homework for this week is to do the enclosed worksheet .pdf.  The answers are included with the .pdf, however, DO NOT look at the answers until you've finished the worksheet!!!!   Use them to check your work.  If you get one wrong figure out why and how to do it right.  I promise you, your quiz scores will be much better if you use this homework as a self quiz type of thing.

Also, if you feel shaky on significant figures or exponential notation, this website has an ugly but effective tool for quizzing yourself.  You might want to check it out.  

Be prepared for a quiz!  Be sure to feel comfy with those metric to english conversions we went over in class.

Never Stop Wondering

"Science Jim"  Mueller

(919) 929-9791

A Fun Approach to Serious Physics!

Sciencejim

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10/12 Chemistry update and homework due 10/19

Hi folks,

This week we did more with density and spent some time with densities brother buoyancy.  We worked quite a bit with the formula for density d=m/v. 

Homework for this week is: 

Read pgs. 1-16

Complete the enclosed worksheet.

Chem update 10/5 and homework due 10/12

Hi folks,

This week we worked on the fairly difficult concept of density. I had the students find the volumes of a block, a cylinder, and a sphere using measurements and math. We also found the volume of several more objects by immersing them in water and seeing how much water was displaced. After finding many volumes, we then went on to take a look at the density of the different objects.

Homework for this week is:

Finish finding the densities of the different objects we measured in class (if you didn't finish that already during class).

Read pgs. 26-28 including the part in green on page 27.

Do questions #41-44 on pg. 33
Do problems # 5 and 6 on page 35

CAUTION: Be ready for a quiz!!!!

9/28 Chemistry Update and homework due 10/5

Hi folks,

Each week after class, I'll email parents and students with updates and the homework assignment that's due the following week.  I will also be updating a blog with the same information so that you can check there as well if you don't want to wander through old emails for information.  Here is the link to the blog site http://sciencejimschemistry2012.blogspot.com/

The past couple of weeks in chemistry we've been doing a quick overview of what science is and how science is done.  Discussing the the definition of science, the scientific method, variables of an experiment and more.  

Homework this week is to write up the lab report for the pendulum experiment that you created.  I've included the .pdf of the lab report template.  We'll be using this template throughout the year.  Please don't hesitate to email me if you have any questions.