Exam 1- through EKG lecture 1 Flashcards
Circuit
collection of elements or elements and signals connected together for purposes of modifying input signals to obtain other desired signals or responses
Electric Current
flow of charges per unit time
Electric Voltage
potential difference measured between 2 points. Expression of potential energy required to move a charge of one coulomb from point A to point B
Ohm’s Law
V=IR
Ohm’s Law Corollary/Darcy’s Law
P(pressure)=Q(flow)R(resistance)
Voltage Analogs
Pressure P (dynes/cm2), temperature T (C), solute concentration C (mg/ml)
Current I(amperes) Analogs
Flow V (cm3/sec), Heat Flow q(Watts), solute flow Q(mg/min)
Frequency
1/Period(T)
Period
1/frequency (f)
Coulomb’s Law
F=k(q1xq2/d^2), The greater the distance between the charges, the weaker the force
Power
P=IV
Kirchhoff’s Voltage Law
The sum of the voltage variations around a loop is 0.
Kirchhoff’s Current Law
The sum of all currents that converge on a node will be 0.
Parallel Resistance
1/R= 1/R1 + 1/R2 + 1/R3…
Series Resistance
R= R1+R2+R3…
Transducer
Converts one form of energy to another form
Wheatstone Bridge
V=0 when R1xR4=R2xR3
Capacitance
“compliance”- the ratio of change in an electric charge in a system to the corresponding change in its electric potential
Parallel Capacitance
C=C1+C2+C3
Inductors - Inertance
Measure of the pressure gradient in a fluid required to cause a change in flow rate with time
Series Inductance
Added together
Parallel Inductance
same formula as parallel resistance
Most circulatory systems
are parallel systems
I=V/R
Q=P/R