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Flashcards in Ohmers Law Deck (20):
1

Ohms Law

V=IR
Voltage =current x resistance (impedance)

2

Define voltage

Electromotive force or the force that drives electron flow

3

Define current

Flow of electrons

4

Define resistance

Resistance to current flow measured in ohms=impedance

5

Furmans formula

E=IR

E represents electromotive force

6

Define series

Beginning of one resistance is connected to the end of another

7

Formula for sum of resistances

R1+R2=total resistance

8

What type of lead issue does series resistance issue indicate ?

Lead fracture or loose set screw (increased impedences)

9

State how to determine voltage drop across a resistance

Determine the ratio of R1 to R2 to determine the percentage drop across each point

10

When are resistances said to be in parallel?

Resistances are said to be in parallel when ALL resistances are connected to the SAME point

11

List the formula for parallel resistances

R1 x R2/R1+R2

12

Give an example of resistances in parallel

Lead insulation defect (low impedance)

13

Does a lead fracture cause an increase or decrease in impedance?

INCREASE in impedance

14

Does a lead insulation defect cause an increase or decrease in impedance?

DECREASE

15

List normal lead impedance

400-600 ohms

16

Do PPMs use constant voltage or current?

Constant voltage ppm
Constant current for most temp pacers but some are constant voltage

17

To what does the term Load refer?

Impedance or resistance applied to a circuit

18

Is a system with a small load applied to a circuit considered constant current or constant voltage?

Constant current

19

Is a system with a large load considered to be a constant current or constant voltage device?

Constant voltage

20

Give an example of series resistance defect

Lead fracture ( high impedance)