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How voltage, current and resistance relate ?. Students Prepare : Abdullah Al Asfour . Samer Al Gamdi. How voltage, current and resistance relate ? By Ohm’s Law. Introduction :. Voltage and Current analogy :. Current :. - It is the rate of flow of charge . - The symbol is I .
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How voltage, current and resistance relate ? Students Prepare : Abdullah Al Asfour . Samer Al Gamdi .
How voltage, current and resistance relate ? By Ohm’s Law ..
Current : - It is the rate of flow of charge . - The symbol is I . - It is measured in amps (ampere) A . (for example I=5 A or I=5 amps) . - Current cannot flow without voltage .
Voltage : - It is a measure of the energy carried by the charge . - It attempts to make a current flow . - The Symbol is : V or E . • - It is described as a “push” of the electric current . • - It is measured in Volts (V=1.5v) .
Voltage : Voltage is supplied by ..
Resistance : - It is the impedance of the current flow . - The symbol is R . - All electrical equipment has an internal resistance . • - It is measured in ohms Ω .
Ohm's Law : - To make a current flow through a resistance there must be a voltage across that resistance . - Ohm's law shows the relationship between the voltage (V), current (I) and resistance (R) . - V = I * R - I = V / R - R = V / I .
How to increase the flow rate without change the resistance ?
Exercises : Q1 : A 3 V is applied across a 6 ohm resistor, what is the current ? Q2 : lamp connected to a 6 V battery passes a current of 60 mA, what is the lamp's resistance ? Q3 : A 1.2 k ohm resistor passes a current of 0.2 A, what is the voltage across it ?
Exercises : A1 : A2 : A3 :
Summery - Voltage measured in volts, symbolized by the letters “E” or “V” . - Current measured in amps, symbolized by the letter “I” . - Resistance measured in ohms, symbolized by the letter “R” . - Ohm’s Law : V = I * R - I = V / R - R = V / I .
Recommended websites : - http://www.the12volt.com/ohm/ohmslaw.asp . - http://www.allaboutcircuits.com/vol_1/chpt_2/1.html . - http://www.physics.uoguelph.ca/tutorials/ohm/Q.ohm.intro.html .