Click the reset button and start with two bubbles. Load a first balloon by rubbing it on the sweater, then move it to the second balloon. Why doesn`t the second balloon move? True or false – A polarized material must have a non-zero net electric charge. [AL] Ask yourself what other examples of polarization come to mind in everyday life. Describe the strength between two interacting positive point charges. Van de Graaff generators are used to demonstrate many interesting effects caused by static electricity. Touching the globe gives a person an excessive load so that their hair stands up on end, as shown in Figure 18.13. You can also create mini-flashes by moving a neutral conductor to the globe. Another favorite is to stack aluminum muffins on the uncharged globe and then turn on the generator. Since they are made of conductive material, the cans accumulate excessive load. Then they repel each other and fly off the globe one by one. A quick search on the internet shows many examples of what you can do with a Van de Graaff generator.
« Electric charge is the property of subatomic particles that makes it undergo a force when placed in an electric and magnetic field. » Electric charges are of two types: positive and negative, usually carried by charge carriers of protons and electrons. Examples of charge types are subatomic particles or matter particles: protons are positively charged. Electrons are negatively charged. Neutrons have no cost. If a person drags their feet on a carpet and then touches a brass doorknob, they may receive an electric shock. If there are enough extra electrons, the force with which these electrons repel each other may be enough to cause some electrons to jump over a gap between the person and the doorknob. The length of the spark is a measure of voltage or “electrical pressure”. The number of electrons moving from one place to another per unit of time, measured as current or “electron flow”. Touching the doorknob with your hand shows a second way of transmitting the electrical charge, which is charged by conduction. This transfer occurs because similar charges repel each other, and so the excess electrons you`ve picked up on the carpet want to be as far away as possible.
Some of them move to the doorknob, where they spread over the outer surface of the metal. Another example of load per line is shown in the top row of Figure 18.10. A metal ball with 100 electrons in excess touches a metal ball with 50 electrons in excess, so that 25 electrons are transferred from the first sphere to the second sphere. Each sphere ends with 75 electrons in excess. This activity studies the repulsion and attraction caused by static electric charge. In this discussion, you may be wondering how the excess electrons originally passed from your shoes in your hand to create the spark when you touched the doorknob. The answer is that no electron actually traveled from your shoes to your hands. Instead, because as charges repel each other, the excess electrons on your shoe simply pushed back some of the electrons in your feet. The electrons that detached from your feet moved into your leg and in turn pushed back some electrons in your leg. This process continued throughout your body until a distribution of excess electrons covered the extremities of your body. So your head, hands, tip of your nose, etc.
all received their doses of excess electrons that had been pushed out of their normal positions. All of this was the result of electrons being pushed out of your feet by excess electrons on your shoes. When a person receives a positive or negative charge, it can cause the person`s hair to stand up because the loads in each hair take it away from the others. If there are an identical number of positive and negative charges, the negative and positive charges cancel each other out and the object becomes neutral. Protons and electrons are therefore the elementary particles that carry the electric charge. Each proton carries a unit of positive charge, and each electron carries a unit of negative charge. With the best precision that modern technology can offer, the charge carried by a proton is exactly the opposite of that of an electron. The SI unit of electric charge is the coulomb (abbreviated as “C”), named after the French physicist Charles Augustin de Coulomb, who studied the force between charged objects. The proton carries +1.602× 10 −19 C. +1.602× 10 −19 C. and the electron carries −1.602× 10 −19 C, −1.602× 10 −19 C,. The number n of protons needed to generate +1.00 C is the polarization can be used to load objects.
Consider the two metallic spheres shown in Figure 18.11. The spheres are electrically neutral, so they carry the same amounts of positive and negative charge. In the top image (Figure 18.11(a)), the two spheres touch each other and the positive and negative charges are evenly distributed over both spheres. We then approach a glass rod carrying an excess positive charge, which can be done by rubbing the glass rod with silk, as shown in Figure 18.11(b). Since the opposite charges attract, the negative charge is attracted to the glass rod, leaving an excess positive charge on the opposite side of the right sphere. This is an example of induction loading, where a load is created by approaching a loaded object with a second object to create an unbalanced load in the second object.