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THE ENERGY STORED IN CAPACITOR

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1. Definition    A capacitor is a device used for storing energy. When we connect a battery across the two plates of a capacitor, it gets charged. The potential difference gradually increases across the two plates and the battery had to do more work to deliver the same amount of charge due to the continuous increase in potential difference. 2. Formula and Example Where: W stands for work (J) C stands for capacitance (F) Q/q stands for charge (C) V stands for electric potential (Volt) Example:    An air-filled parallel plate capacitor has a capacitance of 5.0 pF. A potential of 100 V is applied across the plates, which are 1.0 cm apart, using a storage battery. What is the energy stored in the capacitor? Answer: 3. Important Figure     Pieter Van Musschenbroek was a Dutch physicist who invented the Leyden jar, a device used for storing electrical charges. Musschenbroek was a professor of mathematics and physics at the University of

CAPACITOR

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1. Definition    Capacitors are electrical components that function to store electrical charges. 2. Formula 3. Important Figure    Pieter Van Musschenbroek was a Dutch physicist who invented the Leyden jar, a device used for storing electrical charges. Musschenbroek was a professor of mathematics and physics at the University of Leyden in Holland. Musschenbroek was conducting an experiment in which he poured water into a glass jar and connected the jar by wire to a friction machine that produced static electricity. The device, which was later named the Leyden jar, is stated to be the prototype of capacitors. 4. Uses in Everyday Life    Capacitors have been used to store electrical energy since the late 18th century. Benjamin Franklin was the first to coin the phrase "battery" for a series of capacitors in an energy store application. Individual capacitors generally do not hold a great deal of energy, providing only enough power for electronic

ELECTRIC POTENTIAL

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1. Definition    Electric potential is the magnitude of the electric potential energy for each charge. 2. Formula     Where: V is the electric potential (Volt) k is a constant with a value of  8.99 x 10 9 N m 2 /C 2   q is the charge of each object (C) r is the distance between the charges (m) 3. Important Figure        Alessandro Volta was a physicist, chemist, and a pioneer of electrical science. He is most famous for his invention of the electric battery. He discovered that electric potential in a capacitor is directly proportional to electric charge and in recognition of Volta's contribution to science, the unit of electric potential is called the volt. 4. Uses in Everyday Life    A battery powered electric circuit has locations of high and low potential. A charge moving through the circuit will experience charges in electric potential as it moves locations. In a battery there is an electric field established between the two termina

ELECTRIC FIELD

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1. Definition   Electric field is the area around the electric charge where the charged particles in it experience electrostatic force. 2. Formula  3. Important Figure  James Clerk Maxwell was a Scottish physicist who examined Faraday's ideas concerning the link between electricity and magnetism interpreted in terms of fields of force, Faraday had shown that when a wire moves within the field of a magnet, it causes an electric current to flow along the wire. Maxwell took Faraday's experimental discoveries in the field of electromagnetism and provided a mathematical explanation, which outlined the relationship between magnetic and electric fields. He published his 'Dynamical Theory of the Magnetic Field' in 1864 and in 1873 he published 'Treatise on Electricity and Magnetism' . 4. Uses in Everyday Life   Faraday cages are built by taking a conducting material and forming an enclosure, as shown in the picture above, the pers

ELECTRIC FORCE

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  1. Definition  Electric force is the attractive force or the repulsion force between two charges of the same or opposite type where the force is directly proportional to the sum of the two charges and inversely proportional to the square of the distance. 2. Formula and Example Where: F is the electric force (N) q1 and q2 are the signed magnitudes of the charges (C) r is the distance between the charges (m) k is the Coulomb's constant 9 × 10 9  Nm 2 ·C −2 Example:  A positive charge q exerts a force of magnitude -0.20 N on another charge -2q. Find the magnitude of each charge if the distance separating them is equal to 50  cm. Solution: F = k (q) ( - 2q) / r 2 , r = 0.5 m , F = - 0.20 N , - 0.2 = - 2 q 2 k / 0.5 2 q 2 = 0.2 × 0.5 2 / (2 k) q = √ [ (0.2 × 0.5 2 / (2 × 9 × 10 9 ) ] = 1.66 × 10 -6 C q = 1.66 × 10 -6 C , -2 q = -3.23 × 10 -6 C  3. Important Figure  Born on June 14, 1736, in Angoulême, France, Charles-Augustin de