Transcript IPC Bell

CURRENT ELECTRICITY
Vocabulary
Potential difference (ΔV)
Current (I)
 Conventional current
Resistance (R)
Electric Circuits
Closed loop from/to
battery
Charges lose PE
Series vs. parallel
In series circuits…
Current is the same
throughout
Voltage drops with each
resistor
VT = VA + VB, etc.
In series circuits…
Req = RA + RB, etc.
Practice Problem
How to use…
Voltmeter
Ammeter
Circuit diagram
With multimeter, current
probe
Parallel Circuits
Multiple paths for current flow
 Voltage same for each branch
 Current depends on resistance
Equivalent Resistance
(Parallel)
1/Req = 1/RA + 1/RB...
Summary
Current
Voltage
Res.
Series
same
different
Req = RA + RB...
Parallel
different
same
1/Req = 1/RA +
1/RB...
Practice
Problem
“Combo” Circuits
1. Draw schematic
2. “Condense” resistors
3. Calculate Req for “new”
circuit
4. Etc.
Practice Problem
End Day 1
3/24 and 25/2015
Warm-up
Back of “Electricity
Questions”
1, 2, 3
By yourself or with a buddy
Electric Charge
Conservation law – never created
or destroyed
Charging by Conduction
Charging by
Induction
Charging by
Induction
Coulomb’s Law Problems
3 charge problems
“Short” Circuits
Low resistance circuit –
frayed cord, etc.
V=IR
Short Circuit
Safety Devices
Fuse
Circuit breaker
GFCI
Electric Power
Rate of energy transfer
P = IV
Unit – Watts
Practice Problems