Physical Science 20 - April 30

Today we started our new unit on Physics and particularly light. Before that though I handed out another assignment on Heat and enthalpy in particular. This was called Assignment H5 and students are to hand it in tomorrow to be marked.  If you were absent today, you can find this assignment in the Heat folder in the course notes link.

We talked about the different properties of light and started looking at the speed of light in particular.  We learned that light travels very fast in a vacuum (300 million meters per second) and this makes calculating distances of very far objects easy.  These distances are called astronomical distances and we went over the definition of a parsec, a light year, and an astronomical unit.  We then looked at an example using these and students were assigned Homework 2.2.  Homework 2.2 will be due at a later date though due to Assignment H5 though.

There is a new powerpoint that students can download to get the notes for this unit.  It is found in the Physical Science 20 link on the right and the notes are in the Physics folder called Physics Notes.  We went through slides 1-7 today.  Tomorrow we will be looking at the rectilinear propagation of light.

Physics 30 - April 30

Today we did Lab 3.2 which was on using uniform circular motion to measure the mass of an object that causes that motion.  Students collected data today and started analyzing that data.  Tomorrow we will continue analyzing that data and I will talk about what that should look like.

For students who were absent today, you can find 3 sets of sample data in the Unit 3 folder of the course notes.  Use only 1 of those sets.  If you need help analyzing the data, there is a handout in the same folder labelled, Lab 3.2 Analysis Aid.  Use it to help analyze your data.

Physical Science 20 - April 29

Today in class we discussed the analysis for the lab that we did yesterday.  Students then used the remainder of the class to work on their lab reports.  These are due tomorrow.  Students who were absent for the lab yesterday can still complete the lab if they use the sample data that is able in the Heat folder of the course notes.  Look in the link on the right hand side of the webpage.  Tomorrow we are going to get started on the Physics unit.

Physics 30 - April 29

We had a work period today in class due to a meteor strike and Knievel had to calculate the chances of us surviving so he could not teach today. Pysch! Students were away for retreat today so we decided not to move on.

Physical Science 20 - April 28

Today in class we went over Assignment H4.  The answers are posted in the heat folder of the course notes link.  Afterwards, students completed Lab H1 where they determined the specific heats of 5 different metals.  Students just gathered information today.  Tomorrow we will talk about analysis and when the lab will need to be completed.

Physics 30 - April 28

Today in class we finished looking at planetary motion and how it relates to uniform circular motion. This involved some of the equations I introduced yesterday.  We then went through examples 26 and 27 and students than had the remainder of class to work on Assignment 3.8.  Tomorrow, with most students away at retreat, we will just have a work period.

Physical Science 20 - April 27

Today we went over a couple of examples that showed us how to use Hess's Law.  These examples were different than the ones given in class and allowed us to outline the process of Hess's Law.  After those examples, students then worked on Assignment H4 (Period 2 was assignment the even questions, period 4 was assigned the odd questions) for the remainder of the period.  This assignment will be checked tomorrow.  Tomorrow we are going to be doing Lab H1 on specific heats.

Physics 30 - April 27

Today we started looking at planetary motion and Newton's Law of Universal Gravitation.  This law states that there is a force that exists between any two objects that have mass.  This force is proportional to their mass and inversely proportional to the square of the distance between the masses.  We did examples 24 and 25 which used this law.  We then looked at how gravity causes uniform circular motion, particularly with objects in orbit around planets and stars.  This is called gravitational motion.  It is born from the fact that the centripetal force that causes the motion is supplied by gravity.  We derived some interesting relationships with this fact. We didn't quite get to assignment 3.8 but will tomorrow after we look at a couple of examples.

Physical Science 20 - April 23 & 24

Yesterday we went over Assignment H3 and took up some questions that students had with that.  The remainder of the period I allowed students to study for the heat quiz which was today.  After students wrote the heat quiz today, we learned about enthalpy changes and how to calculate them in a chemical reaction.  This involved using Hess's Law, where you break a chemical reaction down into its parts and determine the overall enthalpy change based on the enthalpy change of the individual parts of the reaction.  We didn't quite get to the assignment today, Assignment H4, but we will get there on Monday. Have a good week everyone.

Physics 30 - April 23 & April 24

Yesterday in class we starting to examine uniform circular motion.  This is a type of motion that happens with a constant speed but a changing direction.  A force called the centripetal force causes this type of motion.  We learned how to calculate the centripetal force along with the centripetal acceleration.  We then worked through a couple of examples (#19-23) today and students finished the class by working on Assignment 3.7.  On Monday we are going to begin to look at gravitational motion.

Physics 30 - April 22

Today we did Lab 3.1 where we measured the coefficient of friction of our shoes.  Students collected data today and started the lab write up, which are due on Friday.  Tomorrow we are going to start to look at centripetal motion.

Physical Science 20 - April 22

Today we learned how to do calculate the heat absorbed or released during phase changes and temperature changes.  These are combined heat problems where we have to do multiple steps to solve the heat value.  We worked through one example (covered on slides 20-27) and then students worked on Assignment H3 for the remainder of the class.  This assignment will allow students to prepare for the quiz on heat which will be on Friday.  Assignment H3 is due tomorrow.

Physical Science 20 - April 21

Today we learned how to calculate the heat involved in changing phases of different substances.  Much like yesterday's lesson, this is dependent on the mass of the substance involved and the type of the substance.  It is not dependent on a temperature change however as phase changes do not involve a temperature change.  Students copied down notes today on slides 12-19 and worked on Assignment H2 for the remainder of the class. I will check this tomorrow and then we will start combine these 2 types of problems.

Physics 30 - April 21

Today in class we had a work period to work on Assignment 3.6.  Most students worked on Assignment 3.5 today.  Make sure you get caught up in the course work.  Tomorrow we are doing Lab 3.1 where you are measuring the coefficient of friction of your shoes.

Physics 30 - April 20

Today we finished Example 17 which we started last Thursday and we also did Example 18.  Both involved looking at how friction works on an incline or a ramp.  Tomorrow students will have the opportunity to work on Assignment 3.6.

Physical Science 20 - April 20

Today in class, students handed in Assignment 1.1 on solving word problems.  As well, I checked Homework 1.2 on manipulating formulas.  After that, we got started on learned about how to measure quantities of heat.  We learned about specific heat capacities and what changes in heat energy depends on.  This was all related by a nice formula that allowed students to see the heat energy gained or lost is dependent on the substances mass, its temperature change and its specific heat capacity.  This was all covered in the powerpoint called Measuring Quantities of Heat which is located in the Heat Folder of the Physical Science 20 Course Notes link.  We covered slides 1-11 and students then worked on Assignment H1 for the rest of the class.  When we got to some examples though of using the formula, we only did examples 1, 2, 5, and 7.  I will check Assignment H1 tomorrow and we will move on to look at what happens to heat in a phase change.

Physics 30 - April 16

Today we finished up our notes on static and kinetic friction and looked at an example of friction in two dimensions.  We did examples 15, 16 and started example 17. This was covered on slides 49-56 in the powerpoint. Students will get some time tomorrow to work on Assignment 3.5. Tomorrow as well we are having the quiz for Lab 2.1.  Make sure you understand the analysis for the lab report.

Physical Science 20 - April 14

Today in class we finished the notes on Kinetic Molecular Theory (KMT).  This means we did slides 9-25 in the powerpoint labelled kinetic molecular theory.  We finished these notes rather early on in class and instead of moving on I let students study for the Chemistry midterm which is coming up on Thursday.  Tomorrow will also be a work period for the chemistry midterm.

Physics 30 - April 14

Today in class we finished up example 14 about friction.  I was going to continue on but I decided to let the students have the rest of the class to prepare for the in class assignment tomorrow.  Reminder of the in class assignment tomorrow on Assignments 3.1-3.4.

Physical Science 20 - April 13

Welcome back everyone.  I hope everyone had a relaxing break and are ready for the push to the summer.  Today we started the new unit on heat with a look at kinetic molecular theory (KMT).  Students were copying down notes on this from the new powerpoint called Kinetic Molecular Theory found in the folder labelled Heat.  We finished slides 1-9.  Tomorrow I hope to complete the notes on KMT.

Today I handed back the stoichiometry exams to students who wrote them before the break.  Students got to keep them to study from them for the midterm we are having on Thursday.  Make sure you are preparing for that midterm.

Physics 30 - April 13

Welcome back everyone from the Easter break - the last long break before the summer and grad for all of you.  I started class today by reviewing what we have learned in the unit before the break.  I thought this was important because most students probably didn't look at physics over the break.  Students should make sure they work through Assignments 3.1-3.4 before Wednesday as we have our first in class assignment in this unit then.  

Today we continued on the unit by looking at friction and how friction works.  We talked about what friction depends on and then we studied kinetic friction specifically.  We did example 13 in the notes and then started example 14.  Tomorrow we will finish example 14 and then look at static friction.  

Physical Science 20 - April 1

Today I checked Assignment C26 and then students worked on their lab reports for the remainder of the period.  The lab reports for Lab C4 are due tomorrow.  As well, tomorrow we are going to have an open book exam on stoichiometry.  Make sure to study Assignments C24 to C26.

Physics 30 - March 31 & April 1

Yesterday in class we learned about Newton's Third Law of Motion, or the action-reaction law.  We learned about the implications of such an important law and how often we use this law and don't realize it.  I assigned Assignment 3.3 at the end of the class.

Today we started to look at specific types of forces.  We began with an examination of the force of gravity.  This is also called an object's weight, although not to be confused with an object's mass.  The one lesson I wanted students to learn today is that mass and weight do not mean the same thing.  Mass is a measure of the amount of matter an object has whereas weight is the force of gravity on that object.  One is measured in kilograms, the other in newtons. 

We learned about the differences between weight and the normal force and also learned what exactly a bathroom scale is measuring.  The concept of apparent weight is really important for students to understand.  This was all covered on slides 36 to 42.  Students were given some time to work on Assignment 3.4 at the end of class, which we will take up tomorrow. 

Physical Science 20 - March 31

Today in class we finished up stoichiometry by looking at percent yield problems.  These are situations where you are given a certain amount of reactant and also given how much product that produces in an experiment.  Using stoichiometry, one can figure out how much product you should have produced, but due to experimental design and setup, these values are always more than what the experiment yielded.  We figured out how to calculate the percent yield of these situations.  These values should always be less then 100%.  These notes were covered on slides 26-30 in the notes and students then spent the rest of class working on Assignment C26 which will be checked tomorrow.