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Flashcards in DC Principles Deck (45)
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1

What are the names and units for; Charge Current Voltage

Charge (q) - coulomb (C) Current (i) - Ampere (A) Voltage (v) - Volt (V)

2

A current is a....

Coulomb per second

3

A volt is a...

Joule per coulomb

4

What's the charge on an electron?

-1.6x10^-19C

5

Current(i) = ?

i(t)=dq(t)/dt = Charge/Time

6

Total charge through a conductor q(t) = ?

q(t) = t(integral)t0 i(t)dt + q(t0)

7

Voltage is...

The energy transferred per unit charge that flows through the element

8

A watt is a...

Joule per second

9

Power =

Voltage x Current

10

If energy is ____ it is positive but if it is supplied it is ____

If energy is absorbed it is positive but if it is supplied it is negative

11

Equation to calculate the power delivered to a circuit element between time instants t1 and t2

w = t2(intergral)t1 p(t)dt

12

The net current entering and leaving a node is?

0

13

State Kirchoff's Voltage Law

The algebraic sum of the voltages equals zero for any closed path (loop) in an electrical circuit

14

In conductors, the voltage between any 2 points of an ____ conductor is ____ regardless of the current

In conductors, the voltage between any 2 points of an ideal conductor is zero regardless of the current

15

When 2 points are connected by an ideal conductor they are ____ together

Shorted

16

There is an open circuit between two parts of the circuit when?

There are no conductors or other circuit elements connected between 2 parts of a circuit

17

Dependant voltage sources (also knows as ____ ____ ____) are represented by?

(Controlled voltage sources) Diamond shapes

18

Resistance = ? and ?

R=V/I and R=(pL)/A

19

Voltage is ____ to ____ in an ideal resistor

Voltage is proportional to current in an ideal resistor

20

Typical values of resistivity for Conductors = conductors = Insulators =

Conductors = 10^-8 conductors = 0.1 Insulators = 10^21 ('infinity')

21

Conductance is? and so (Symbol, equation and unit)

G which is 1/R and so Ohms^-1 and so i=Gv

22

Energy = ? (for a battery)

Q.v

23

Q = ?

i.T

24

Energy = ? (2 obvious ones)

mgh and 1/2mv^2

25

Energy density = ?

Energy (J) / Mass (kg)

26

Conductances in series and parallel is...?

Opposite to resistance

27

Voltage divider?

V1 = R1 x i = R1 / (R1+R2+R3) x Vtotal

28

Fraction of voltage is ratio of...?

Given resistance / total resistance

29

Fraction of current is ratio of...?

Other resistance / total resistance

30

For current division - i1 = ? and i2 = ?

i1 = v/R1 = R2/R1+R2 x itotal and i2 = v/R2 = R1/R1+R2 x itotal