CHARGE<\/h3>\n
All objects surrounding us (including people) contain a large amount of electric charge. A charge can be negative or positive and it is measured in the unit called coulombs (C). However, objects can either be electrically neutral or electrical charged.<\/p>\n
A charge has three important properties which are;<\/p>\n
- \n
- A charge is always conserved. Charge, just like energy, cannot be destroyed nor created.<\/li>\n
- The charge comes in discrete packets. The smallest unit of charge is that carried by one electron called the elementary charge, e, and by convention, it has a negative sign (e= -1.6 x 10-19C)<\/li>\n
- Charge object exerts electrostatics forces on each other. Like charges repel and unlike charges attract each other.<\/li>\n<\/ol>\n
There are three (3) ways of charging a neutral body;<\/p>\n
- \n
- By Friction:<\/strong> This is the act of rubbing two bodies together so that each of the body losses or gains charge. The one that loses charge becomes positive while the one that gains charge becomes negative.<\/li>\n
- By Contact:<\/strong> Bringing two bodies together.<\/li>\n
- By Induction:<\/strong> The process of bringing two bodies together from far while a charge takes place. Charging by induction requires no contact with the object inducing the charge and the object is left with the opposite charge.<\/li>\n<\/ol>\n
COULOMB\u2019S LAW<\/h3>\n
The behavior of the electrostatic force was studied in detail by Charles Coulomb around 1784. Through his observation, he was able to show that the electrostatic force between two point-like charges situated in a vacuum is inversely proportional to the square of the distance between the objects. He also discovered that the force is proportional to the product of the charges on the two objects.<\/p>\n
\u201cCoulomb\u2019s law states that in a given medium, the force of attraction or repulsion \u201cF\u201d between two bodies will charge \u201cQ and q\u201d is directly proportional to the product of the charge and inversely proportional to the square of its distance \u201cr\u201d<\/em><\/strong><\/p><\/blockquote>\n
<\/p>\n
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<\/span><\/p>\n<\/p>\n
\u00a0ELECTRIC FIELD<\/h3>\n
- \n
- Isolated Charge: <\/strong>A charge is said to be isolated when it is standing on its own (either positive or negative charge)<\/li>\n<\/ul>\n
![\"\"](\"https:\/\/i0.wp.com\/www.helpingstudents.com.ng\/wp-content\/uploads\/2017\/12\/Positively-Isolated-Charged-Body-_-HELPING-STUDENTS-300x300.jpeg?resize=300%2C300\")
<\/span><\/p>\n<\/p>\n
- \n
- A line of force for two like charge.<\/strong><\/li>\n<\/ul>\n
![\"\"](\"https:\/\/i0.wp.com\/www.helpingstudents.com.ng\/wp-content\/uploads\/2017\/12\/Two-Like-Charge_HELPING-STUDENTS-300x153.jpeg?resize=300%2C153\")
<\/span><\/p>\n<\/p>\n
- \n
- A line of force for two unlike charged body<\/strong><\/li>\n<\/ul>\n
![\"\"](\"https:\/\/i0.wp.com\/www.helpingstudents.com.ng\/wp-content\/uploads\/2017\/12\/Two-Unlike-Charged-Bodies-_-HELPING-STUDENTS-300x191.jpeg?resize=300%2C191\")
<\/span><\/strong><\/p>\n\u00a0CAPACITORS<\/h3>\n
These are electrical\/electronic devices use in storing charges in the form of electrical energy. There are three (3) major types of capacitors namely;<\/p>\n
Ceramic Capacitors:<\/h4>\n
They are small in size and value, ranging from a few Pico Farads to 1 \u00b5 Not polarized, so either end can go to the ground. Value is given by a mystical code somewhat like that of resistors.<\/p>\n
![\"\"](\"https:\/\/i0.wp.com\/www.helpingstudents.com.ng\/wp-content\/uploads\/2017\/12\/Ceramic-Capacitors-_-HELPING-STUDENTS-300x140.jpeg?resize=300%2C140\")
<\/span><\/p>\nElectrolytic Capacitors:<\/h4>\n
They look like small cylinders and range in value from 1 \u00b5F to several Farads. Very inaccurate and change in value as the electrolytic ages. Polarized, the cathode must go to the ground. A cathode is marked with a minus sign on the case. Value is usually written on the case.<\/p>\n
![\"\"](\"https:\/\/i0.wp.com\/www.helpingstudents.com.ng\/wp-content\/uploads\/2017\/12\/Electrolytic-Capacitors-_-HELPING-STUDENTS-300x229.jpeg?resize=300%2C229\")
<\/span><\/p>\nTantalum Capacitors:<\/h4>\n
They are similar in size to ceramic but can hold more charge, up to several hundred \u00b5 Accurate and stable, but relatively expensive. Usually polarized, an anode is marked with a plus sign.<\/p>\n
![\"\"](\"https:\/\/i0.wp.com\/www.helpingstudents.com.ng\/wp-content\/uploads\/2017\/12\/Tantalum-Capacitors-_-HELPING-STUDENTS-300x294.jpeg?resize=300%2C294\")
<\/span><\/p>\nOther common types of capacitors are Mayer capacitors, Percept\/variable capacitors, Paper capacitors, Parallel plates capacitors etc\u2026<\/p>\n
USES OF CAPACITORS<\/h4>\n
- A line of force for two unlike charged body<\/strong><\/li>\n<\/ul>\n
- A line of force for two like charge.<\/strong><\/li>\n<\/ul>\n
- By Contact:<\/strong> Bringing two bodies together.<\/li>\n
- By Friction:<\/strong> This is the act of rubbing two bodies together so that each of the body losses or gains charge. The one that loses charge becomes positive while the one that gains charge becomes negative.<\/li>\n