Ch18_JohnsonR

= = toc = = = __Guiding Questions:__ =


 * 1. What is the structure and properties of an atom? **

// An atom is made up of two parts, a nucleus and a cloud of electrons moving around the nucleus. The nucleus is made up of equal amounts of neutrons, which hold no charge, and protons, which hold a positive charge. The cloud of electrons is made up of negatively charged electrons. //


 * 2. What is the symbol and unit of electric charge? **

// The unit of electric charge is known as a Coulomb. The symbol for this is C. //


 * 3. Distinguish between positive and negative charges in as many ways as possible. **

// There are many differences between positive charge and negative charge. One is between their masses. A proton has a mass of 1.67x10-27 kg while an electron has a mass of 9.11x10-31 kg. Due to the difference in mass the protons are immobile while the electrons // // are able to move around freely. //


 * 4. Describe the properties of electric forces. **

// Electric force is a non-contact force. It occurs when a charged object come close to another object either charge or uncharged. In this case opposites attract and likes repel. //


 * 5. Distinguish between insulators and conductors. **

// Conductors are materials that permit electrons to flow freely from atom to atom and molecule to molecule. On the other hand, an isolator is a material that impedes the free flow of electrons from atom to atom and molecule to molecule. //


 * 6. What is polarization? **

// Polarization is when the electrons of an object or moved either to the left side or right side of an object. What this does is make one side of the object positive and the other negative. //


 * 7. How does a neutral object acquire charge? **

// A neutral object acquires a charge when the object either gains or loses electrons. //


 * 8. Distinguish between the 3 charging processes. **

// Charging by friction occurs when two objects are rubbed together. In this case one object will have a much larger electron affinity, or an absolute need for electrons, than the other causing this object to become negative while the object with the lesser electron affinity becomes positive. Charging by inductions is when two neutral objects are touching and then a charge object is put in close proximity to them. What happens is the charged object, for this example a negatively charged balloon, repels all the electron of the closer object into the other. The two objects are then pulled away leaving the further one negative and the closer one positive. The final method of charging is charging by conduction. Charging by conduction occurs when a charged object touches a neutral object. If a positively charged piece of metal was touched against a neutral metal sphere the electrons would be attracted to the extra protons in the piece of metal causing them all to flow to the piece of metal as well as leaving the sphere positively charged. //


 * 9. What is the law of electric charge? **

// The law of electric charge is that the net charge of an isolated system remains constant. //


 * 10. What is an electric field? **

// An electric field is the region around a charge where another charge will feel an electric force. //


 * 11. What are the characteristics and properties of an electric field? **

// An electric field is created around a charged object. When two fields are in close proximity they will either attract each other if the two charges are opposite, or the two fields will repel each other if the charges are the same. There are two variables that will affect the strength of the field and those two are the magnitude of the charge and the distance the two charges are from each other. //


 * 12. What are the “players” involved in an electric field? **

// The players that are involved in an electric field are the many other charges that enter into the field. //


 * 13. What are electric field lines? **

// Electric field lines are a visual representation of the electric field. //


 * 14. What are 4 characteristics of electric field lines? **

// The four characteristics of electric field lines are that lines should never cross one another, lines should enter into the negative and exit from the positive, lines should be perpendicular from the charge, and there should be more lines the larger the charge is. //


 * 15. Go to []. Scroll to the bottom of the page and do the “Check Your Understanding” questions. **

// C, D, and E are all incorrect. C is incorrect because the line are entering into the positive, D is incorrect because it has a symmetrical object with lines that are not placed symmetrically, and E is incorrect because the lines are exiting the negative. //

// What Erin did wrong was she had the electric field lines cross. This is one of the four major rules, which should not be broken. //

// Object A is negative because the lines are going onto it, while object B is positive because the lines are entering it. //

// D,A,E,C,B //

// A (+) B(-) C(+) D (-) E(-) F(+) G(+) H(+) I(+) //

// (A>B)(D>C)(F>E>G)(I>H>J) //

=__ Summary of Lesson 1 __=


 * 1. What (specifically) did you read that you already understood well from our class discussion? Describe at least 2 items fully. **

// What I read that I had already understood was the structure of an atom. I had already known that an atom was made up of a dense nucleus consisting of neutrons and protons as well as a cloud of electrons orbiting the nucleus. I understand that when two objects with the same charge are put by each other they will repel and if they have opposite charges they will attract. //


 * 2. What (specifically) did you read that you were a little confused/unclear/shaky about from class, but the reading helped to clarify? Describe the misconception you were having as well as your new understanding. **

// What I had trouble grasping was the concept of polarization. I had to read it over twice to full understand exactly why the object will seem like it is half positive and half negative. I now know that the presence of a charged object, positive for example, would attract all the electrons to it due to the concept of opposites attracting. This is how the object appears half positive and half negative. //


 * 3.What (specifically) did you read that you still don’t understand? Please word these in the form of a question. **

// How can the protons accumulate to one side of an object if they cannot move? //


 * 4.What (specifically) did you read that was not gone over during class today? **

// In class we did not talk in detail about what objects are conductors and what objects are insulators. //

=__Sticky Tape Lab:__=