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Showing posts from November, 2018

Capacitors

Capacitors Capacito r is a device that is normally used in electrical appliances such as radios, computers and TV. There are many different types(looks) of capacitors as shown below: The function of the capacitor is to store electrical charges. Remember , we have 2 types of charges ( positive and negative). Once the capacitor has stored the charge, it can release electrical energy. I give you an example: The flash unit of camera also uses a capacitor. The fact that the camera can give out the flash, it is actually releasing the energy from the charge that is stored in the capacitor. When we measure something , it must has its own quantity and unit. For example, (i) the length (quantity) of a ruler --> the unit is metre (ii) the mass  (quantity) of a ball --> the unit is  kg Same goes to the capacitor, the quantity measured by the capacitor is capacitance and its unit is Farad.  Scientifically, the meaning of capacitance is the ratio of the amount of  charge

Electric Potential

Electric Potential, V If Ali wants to move his charge towards the charged sphere on the left, he has to push against the repulsive force between the two spheres (because both are positively charged) Ali is actually doing work (when he push) , Remember W= f.s  ! At the same time, Ali's charge gains electric potential energy . If Ali let go his charge, it will move away from the sphere, it looses electric potential energy. The  electric potential  at a point is telling us the  potential energy of each coulomb of charge . When you move a charge in an electric field its potential energy changes. This is analogous to moving a mass in a gravitational field. Electric potential is a scalar quantity. Thank you, Mdm Ummi Atiah KMPk ~  May it Benefits You ➽💕

Electricity: Coulomb's Law

Coulomb's Law The ancient Greeks found that a piece of amber, when rubbed became electrified and attracted pieces of straw or feathers. In 1785, Charles Coulomb describes experiments that confirmed the inverse-square force law of electricity. Coulomb's law is the fundamental law of force. Coulomb's law discusses the force between two stationary charged particles. STATIONARY, please bear in your mind! (we'll learn a different concept for the MOVING charges)  Knowing that, there are two type of charges: that are positive a nd negative charges. The Coulomb force can be attractive and/or repulsive where it depends on the types of charges interacted. Like charges repel one another Opposite charges attract one another Let's understand this example of experiment, an inflated balloon is rubbed with wool . The balloon will then stick to the wall of a room, often for hours (on a dry day). Rubbing the balloon with the wool is equivalent to taking off the neg