Electrostatics and Electricity

Electrostatics Electrostatics is the study of electric charge Electric Charge-is described as electron movement. Electrons can transfer from one object to another Two types of charges + and – Like charges__________ Opposite charges________ How objects become electrically charged is by transfer of electrons

There are two types of electron transfer Conduction- is process of charging a neutral body by touching it with a charged object Induction-process of a charge induced by close proximity to the charged object Electroscope- is a device that detects electric charges

Conductor – is a material in which electrical charges flow easily (ex Insulator – is a material in which electrical charges do not flow easily (ex. ____________) Polarization – the process of rearranging the charges already present on an object to create a temporary charge

Lightning

Van de Graff Generator

Coulomb’s Law Coulomb’s Law – the magnitude of electric force between two charges is directly proportional the magnitude of the charges and inversely proportional to the square of the distance between the charges.

Coulomb’s Law Cont. * a negative force means they were attracting charges *a positive force means they were repelling charges *Coulomb’s Constant =KC= 8.99 x 109 Nm2/C2

Coulomb’s Law Cont. An electron with a charge of 1.60x10-19 C is .10m from a proton with a charge of 1.60x10-19 C . What is the electric force between the two charges? Felect =??? Q1 = - 1.60 x 10-19 Q2 = 1.60 x 10-19 d = .10m

Coulomb’s Law Cont. Two balloons are charged with an identical quantity and type of charge: -6.25 x 10-9 C . They are held apart at a separation distance of .617 m. Determine the magnitude of the electrical force of repulsion between them.

Circuit Schematics Schematic – a diagram that uses symbols for components of an electrical circuit

Types of Circuits Series circuit – all current travels through each electrical component in one path (ex. Christmas lights) Series formulas VT = V1+V2+V3….. IT = I1=I2=I3….. RT = R1+R2+R3…..

Types of Circuits Parallel circuit – a circuit with several paths of current Parallel formulas VT = V1=V2=V3….. IT = I1+I2+I3….. 1/RT = 1/R1+1/R2+1/R3…..

Ohm’s Law Electric current – the flow of charge. Electrons flow around a closed loop called a circuit Electric current is measured in amperes (amps; 1A=1 amp) The symbol of current in the equation is I

Ohm’s Law Voltage – the potential difference in electric charge. Voltage is measured in volts (V) The symbol for voltage is V

Ohm’s Law Resistance – property that determines how much current will flow through a circuit Resistance is measured in ohms (Ω) The symbol for resistance is R in the equation All conductors offer some resistance

Ohm’s Law I=V/R; this is relationship ohm discovered V=IR