Presentation on theme: "Problems due Friday are: Chapter 1 problems: C1B.1, C1B.2, C1B.3, C1B.4, and C1S.5. Thursday the lab will be for each person to measure the height of the."— Presentation transcript:
Problems due Friday are: Chapter 1 problems: C1B.1, C1B.2, C1B.3, C1B.4, and C1S.5. Thursday the lab will be for each person to measure the height of the two flagpoles, write a discussion of your uncertainty in that height and write a discussion comparing your results with two other students. The test over chapters one and two is scheduled for Friday, September 3. Problems due next Wednesday are: Chapter 2 problems: C2B.1, C2B.2, C2B.4, C2B.7, C2B.8, C2B.9 and C2S.1 Ask questions about them Monday.
Lab tomorrow How to measure the heights of the two flagpoles.
Each individual must write on a sheet of paper what he/she thinks science to be. (you have 3 minutes) This is not to test what you learned from out text, this is to obtain your “gut” feeling about science. Your definition must not contain the phrase “scientific method” or a synonym of this term. What sets science apart from the other ways of “knowing” or “learning”. Your group now has 3 min to arrive at a consensus and put your result on the board.
One physicist’s opinion Science is a way to study nature and natural phenomena that uses nature itself as the final authority. The experiment determines who is right. Man’s guess about how God does things. Measurement is a fundamental aspect of science, especially physics.
The cost of using groups Fewer topics covered Students feel the class time is not well utilized, they feel they could have accomplish more in a more structured environment. These disadvantages are offset by the fact that principles and processes are learned better by students of all abilities when they work in groups, resulting in better comprehension and test scores of all students. Including MCAT, GRE, etc
Physics for biologists Studying a physics text is much different than reading a biology text. What is active reading? Being sure you understand the process In this class we are much more interested in the process of arriving at the answer than whether or not you arrive at the correct answer. When you learn the process, the correct answers will come Credit on homework will be given for process even if the final answer is not obtained or is incorrect. For this reason be sure your process is clear from what you put on your paper. The same is true for tests.
Naming the ideas behind physics All the ideas of physics fit into one of two large categories these are: Standard model Everything except gravity Including motion, electricity, thermodynamics, chemistry, biology General Relativity Explains gravity and other long range effects. You should remember these two and when they apply You need not be concerned with the details of the diagrams on pages 6 and 7.
Noether’s Theorem Conservation of energy Means physical laws do not change in time Conservation of linear momentum Means physical laws are the same anyplace in the Universe. Conservation of angular momentum Means physical laws are the same regardless of how you are oriented Same in all directions. The most important idea this year
The structure of matter ( Part of the standard model) Large objects are made of atoms Atoms are made of electrons, protons and neutrons. All these particles are made of elementary particles. Electrons are examples of leptons The proton and the neutron are the only combination of quarks that last more than a millionth of a second. One current theory says that all elementary particles are made of strings (of energy).
This theory accounts for all types of mass. What quarks make the proton? See page 11 What quarks make the neutron?
What is meant by the term “interaction”? Each person is to write in their own words a definition of “interaction”. (3 minutes) Try to use words a non-science person can understand. In your groups arrive at a common answer and put it on the Board.
Gault’s attempt at defining interaction. Something that must happen for one object to affect another object. If there is no interaction between objects, one does not affect the other in any way. Your definition may be better.
Types of interactions Macroscopic Distance Contact Between quarks inside the nucleus Strong nuclear - 1 Weak nuclear - 2 Between charged particles Electromagnetic - 3 Between any particles that have mass Gravitational - 4 Only these four types of interaction exist As far as we know today!
Describe the interactions on the swinging object. Each group has 2 min to name the interactions and then write them on the blackboard
Velocity The speed of an object is the distance traveled per unit time (for example the number of meters per second). We find that interactions do not necessarily change the speed but they always change either the speed or the direction.
Vector It is therefore convenient to define something that includes both the speed and the direction of a moving object. We call this the Velocity. When a physical quantity includes both size (magnitude) and direction, we call it a vector.
Units Learn the standard prefixes from tera to pico. (page – 17 and front cover of text) Always show your units in all calculations. Example: Change grams to English tons (2000 lbs) On both problems and tests, every mark on the above is required!
The unit operator method Suppose there are 3 gob/tow, 7 rem/tow, 5poy/gob and 9 poy/in. 10 in is how many rem? Begin with what you know and eliminate units you don’t want working toward the units you do want.
Units In your groups: Use the unit operator method to calculate the number of seconds in a century. Each person is to do the calculation on a paper in front of them clearly showing all steps. Compare answers at your table. When all at your table agree, write the answer on the board (showing your work).
Problems: You should have been working on these problems. Hand them in at the beginning of lecture on Friday. Chapter 1 problems: C1B.1, C1B.2, C1B.3, C1B.4, C1S.5, and C1R.1
You should have tried the chapter 1 problems. If you have any questions ask them now. They are due as you arrive in class next Wednesday. You should begin work on the chapter 2 problems. Both labs should be finished and handed in today if at all possible. Lab Tuesday will be on vectors. Both labs meet next Thursday.