can you kill yourself with a 9 volt battery?
DESCRIPTION
Can you kill yourself with a 9 volt battery? . Resistivity. Current Density of a conductors depends on Electric Field and the properties of the material Those properties are symbolized with the Greek letter rho and referred to as resistivity The unit for resistivity is Ohm-meters - PowerPoint PPT PresentationTRANSCRIPT
• Can you kill yourself with a 9 volt battery?
Resistivity
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J =Eρ
ρ =EJ
ρ =V mA m2 =
V ⋅mA
=VA⋅m =Ω⋅m
•Current Density of a conductors depends on Electric Field and the properties of the material
•Those properties are symbolized with the Greek letter rho and referred to as resistivity
•The unit for resistivity is Ohm-meters
•Resistivity changes with temperature
Zero-Resistivity Superconductors
Superconductors are used to make medical scanners, magnetometers, and rail guns
Resistivity & Resistance
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R =ρLA
•Unit for Resistance is Ohms (Ω)
•Resistance is higher for wires of longer length
•Resistance decreases with larger cross-sectional areas
Conductance
• The reciprocal of Resistance
• Lord Kelvin called the unit the mho
• Officially the Siemens
• 1 mho = 1 Siemens
Ohm’s Law
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E = ρJVL=IAρ
V = IρLA
V = IR
Units
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V = IRVolts = Amps⋅Ohms
Ohms =VoltsAmps
I-V Graph for Ohmic Material
Diode: Ohmic or Not Ohmic?
Guess the Resistors!