h19 - Chapter 19 The Electric Interaction During the first...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
Chapter 19 The Electric Interaction During the first semester we mentioned that there are four known forces active in the universe. We studied gravity in some detail. This semester starts with the study of the electrical force. We will then study magnetism (which is actually a manifestation of electrical force). Later in the semester we will spend a brief time discussing the strong and weak nuclear forces. page 2 The model of the atom shown at the bottom of the page is OK for the level of this discussion. Later in the course we will discuss a better model of the atom in which the electrons do not have definite orbits like planets around the sun. Why do you think the electric interaction is more important in the atom than for the case of the earth orbiting the sun? Later in this chapter we will perform some calculations that will verify statements made on this page. page 3 Atomic Structure What objects are found in most atoms? Have you ever heard the phrase “cathode ray tube?” Experiments on cathode rays from 1894 – 1897 led to the use of the term “electrons.” Experiments gave evidence for the proton from 1898 through 1919 when the term “proton” was accepted. The neutron was experimentally isolated in 1932. In drawings of atoms, why are the electrons the only objects represented as having motion in the atom? Try to make a scale drawing of an atom. The approximate diameter of the nucleus is 10 -15 meters. The approximate diameter of an atom is 10 -10 meters. What is in between the electron and the nucleus? Are you mostly solid or mostly empty space? Why can’t you push your hand slowly through a table? Gravity only attracts objects. We will see a demo of static electricity that shows that the electrical force may attract or may repel. What circumstances lead to an attractive electrical force? What circumstances lead to a repelling electrical force? A hydrogen atom has one proton and one electron. Is this atom electrically neutral? Why? Carbon has 6 protons in its nucleus. How many electrons does a neutral carbon atom have? What is an ion? How can you create an ion of carbon?
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Does any other element in the periodic table, other than carbon, have 6 protons in its nucleus? For elements that are found on the earth, not man made, the largest atom is uranium, which has 92
Background image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 4

h19 - Chapter 19 The Electric Interaction During the first...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online