Activator: True or false if false correct The basic particles of an atom are protons, neutrons, and nuclei. 2) Particles that make up an atom have No charge. 3) Electrons are negatively charged.
Vocabulary: Sections 1 and 2 • Law of electric charges • electric force • conduction • induction • conductor • insulator • static electricity • electric discharge • 9) grounding • 10) ion
All matter is composed of atoms • Atoms are made of • protons – positively charged particles • neutrons – particles with no charge • electrons – particles with a negative charge
3) A charged particle exerts a force 4) The Law of electric charges says that like charges repel and opposite charges attract.
5) The force between two charged objects is an electric force ;it can be attractive or repulsive. Its strength is determined by the size of the charge and the distance between the charges. -the closer the objects are, the greater the charge
6) Electric force exists because the charged particle has an electric field surrounding it.
7) Normal atoms have NO charge. They become charged when they gain or lose electrons. An atom becomes negatively charged when it gains extra electrons. If an atom loses electrons it becomes positively charged. A positively or negatively charged atom is called an ion.
8) There are three ways to charge an atom: induction conduction friction
9) Friction: rubbing two objects together may cause electrons to be “wiped” from one object to another
10) Conduction: Electrons are transferred when two items have direct contact.
11) Induction: When a charged object is placed near a neutral object it may cause the particles in the neutral object to rearrange themselves.
12) Law of Conservation of charges: No charges are created or destroyed. Electrons move from one item to another
13) Conductors: charges move through easily Insulators: charges do not move through easily Ex: metals
15) Electric discharge: the loss of a charge – sometimes over time, or quickly as a spark or a shock.
16) Lightning is an electric discharge that occurs when charges build up in the clouds.
17) Grounding- provides a pathway to drain excess charge into the Earth; lightning rods provide grounding for many buildings.
Explore Static Electricity(mini lab) How can materials interact electrically? Hold the newspaper strips firmly together at one end and let the free ends hang down. Observe the strips. Put the plastic bag over your other hand, like a mitten. Slide the plastic down the entire length of the strips and then let go. Repeat several times. Notice how the strips of paper are hanging. Describe what you observe.
What do you think? How did the strips behave before step 2? How did they behave after step 2? How might you explain your observations?