Electric Circuits

Question 1

at a given point, this equals the electric potential energy of a test charge (q) situated at that point divided by the charge itself

Answer 1

electric potential voltage (V)

Question 2

Equation: Electric Potential Voltage (V)

Answer 2

V = EPE / q
SI Unit = Joule / Coulomb = Volts (V)
Note: EPE = electric potential energy; q = small test charge

Question 3

Equation: Work done to move a charge from point A to point B / Electric Potential and work

Answer 3

V = W(ab) / q
SI Unit = Joule / Coulomb = Volt (V)
Note: W(ab) = [work done to move a charge from point A to point B]

Question 4

Equation: Voltage / Electric Potential set up by a point charge (q)

Answer 4

V = k * q / r

SI Unit = Volt (V)

Question 5

A positive charge accelerated from a region of ______ potential (+) to a region of ______ potential (-)

Answer 5

higher potential to lower potential

Question 6

A negative charge accelerated from a region of ______ potential (-) to a region of _______ potential (+)

Answer 6

lower potential to higher potential

Question 7

caused by a flow of positive charges opposite the actual movement of electrons, (which are normally the charge carriers in a current)
flows from + toward - (high potential to low potential)

Answer 7

electric current

Question 8

Equation: Electric Current

Answer 8

I = q / t
SI Unit: Ampere (A)
Note: I = current in Amperes = Coulomb / second; q = amount of charge that passes through in time (t)

Question 9

Equation: Ohm’s Law

Answer 9

V = IR
SI Unit: Volts (V) = Ampere / Ohm
Note: V = voltage (potential drop across a piece of material); I = current through the material in Amperes; R = resistance of the piece of material (Ohms)

Question 10

wire or electrical device that offers resistance to the flow of charges

Answer 10

Resistor

Question 11

Symbol: zig zag line in a circuit

Answer 11

resistor

Question 12

Symbol: straight line in a circuit

Answer 12

ideal conducting wire

Question 13

Equation: Electric Power (P)

Answer 13

P = IV
SI Unit = Watt (W)
Note: I = current in amperes; V = voltage (potential drop)

Question 14

wiring the provides the same electric CURRENT through each device

Answer 14

series wiring

Question 15

Equation: Resistors in Series

Answer 15

R(eq) = R1 + R2 + R3….

Note: Use R(eq) in Ohm’s Law when calculating voltage for circuit w/ resistors in series

Question 16

Equation: Capacitors in Series

Answer 16

1 / C(eq) = 1/C1 + 1/C2 + 1/C3….

Question 17

wiring that provides the same VOLTAGE through each device

Answer 17

parallel wiring

Question 18

Equation: Resistors in Parallel

Answer 18

1 / R(eq) = 1/R1 + 1/R2 + 1/R3….

Note: Note: Use R(eq) in Ohm’s Law when calculating voltage for circuit w/ resistors in parallel

Question 19

Equation: Capacitors in Parallel

Answer 19

C(eq) = C1 + C2 + C3….

Question 20

device for measuring current
connected in series
has zero resistance ideally

Answer 20

ammeter

Question 21

device for measuring voltage between two points
connected in parallel
has infinite resistance ideally

Answer 21

voltmeter

Question 22

devices that are capable of storing electric charge

Answer 22

capacitors (C)

Question 23

Equation: charge stored by a capacitor

Answer 23

q = CV
SI Unit: Coulomb / Volt = Farad (F)
Note: q = charge on each plate in capacitor; V = voltage difference b/w the plates or voltage; C = capacitance

Question 24

two conductors of any shape (ex: parallel metal plates) that are placed near each other without touching
stores electric charge
SI Unit: Coulomb / Volt = Farad (F)

Answer 24

capacitor

Question 25

Equation: Capacitor w/ 2 parallel plates

Answer 25

C = e(o) * A / d
SI Unit: Coulomb / Volt = Farad (F)
Note: C = capacitance; A = area of the plate; d = distance between two plates; e(o) = permittivity of free space

Question 26

Permittivity of free space: e(o)

Answer 26

e(o) = 8.854 * 10^-12 F / m

Question 27

Equation: Charge stored by a parallel place capacitor

Answer 27

q = C(p) * V
SI Unit = Coulomb
Note: C(p) = C1 + C2 + C3….

Question 28

Equation: Electric Potential Energy of a Capacitor (3 equations)

Answer 28

U = 1/2 * C(p) * V^2 
U = 1/2*QV 
U = 1/2 * Q^2/C

Question 29

Equation: charge stored by Capacitors in series

Answer 29

q = C(s) * V
SI Unit = Coulomb
Note: q = charge on each capacitor in series; C(s): 1 / C(s) = 1/C1 + 1/C2 + 1/C3….