Physics Facts Flashcards
1
Q
What is the worst frequency for electric shocks?
A
50Hz
2
Q
What current is a microshock?
A
100-150 µA
3
Q
What would a current of 1 - 5 mA cause?
A
Tingling
4
Q
What would a current of 5-10 mA cause?
A
Pain
5
Q
What would a current of 15 mA cause?
A
Can’t let go
6
Q
What would a current of 50mA cause?
A
Respiratory arrest
7
Q
What would a current of 100 mA cause?
A
VF
8
Q
What is the maximum leakage current for 1B equipment?
A
500 µA
9
Q
What is the max leakage current for type 2B equipment?
A
100 µA
10
Q
What is the max leakage current for 1BF equipment?
A
500 µA
11
Q
What is the max leakage current for 2BF equipment?
A
100 µA
12
Q
What is the max leakage current for 1CF equipment?
A
50 µA
13
Q
What is the max leakage current for 2CF equipment?
A
10 µA
14
Q
What is the wavelength of red light?
A
660 nm
15
Q
What is the visible spectrum of light wavelengths?
A
400 - 700 nm
16
Q
What is the wavelength of infrared light?
A
940 nm
17
Q
What are the isobestic points?
A
590 and 805 nm
18
Q
What is the pulsatile component of pulse oximetry?
A
2% total absorbance
19
Q
What is an alpha particle?
A
2N + 2E
20
Q
What is a beta particle?
A
E
21
Q
What is a gamma ray
A
>1019 Hz
22
Q
What is the frequency of Xrays?
A
1013 to 1019 Hz
23
Q
What is the wavelength of CO2 (infrared) lasers?
A
10600 nm
24
Q
What is the wavelength of ND-YAG (red) lasers?
A
1200 nm (vascular)
25
What is the wavelength of argon (blue-green) lasers?
500 nm (retinal)
26
What is the maximum flow rate of a 22G cannula?
40 ml/min
27
What is the maximum flow rate of a 20G cannula?
70 ml/min
28
What is the maximum flow rate of a 18G cannula?
110ml/min
29
What is the maximum flow rate of a 16G cannula?
240ml/min
30
What is the maximum flow rate of a 14G cannula?
270ml/min
31
What is the frequency of deep US?
2-4 MHz
32
What is the frequency of detailed US?
4 - 10 MHz
33
What is the frequency of diathermy?
1 - 5 MHz
34
What is the mains frequency in UK?
50Hz
35
What is the frequency of an A-line?
0.5 - 40 Hz
36
What is the frequency response of an ECG?
0.5 - 80Hz
37
What's the sweep speed of an ECG?
25 mm/s
38
Whats the calibration of an ECG?
1 mV/cm
39
What is CM5 sensitivity?
90% ST changes in LV
40
Where do the leads go in CM5 configuration?
Red - Manubrium
Yellow - V5
Green - left shoulder
41
What size filter is on a blood giving set?
200 µm
42
What size filter on a standard giving set?
15 µm
43
What size filter on a filter needle?
5 µm
44
What size filter on an epidural and HME?
0.2 µm
45
What size filter for viruses?
\< 0.1 µm
46
What size filter for bacteria?
1 µm
47
What size filter for platelets?
2 µm
48
What size filter for RBCs?
7 µm (deform at 3 µm)
49
What size filter will remove WBCs?
10 µm
50
What are the electrodes in a galvanic fuel cell?
Gold
Lead
Potassium hydroxide
51
What are the electrodes in a Clark (polarographic)?
Platinum
Silver
Potassium Chloride
52
What electrodes does a CO2 (severinghaus) electrode have?
Glass
Silver
HCO3
53
What are the infrared spectroscopy wavelengths of volatiles?
8-9 µm IR
54
What are the IR spectroscopy wavelengths of H2O, N2O and CO2?
H2O 4.6 µm IR
N2O 4.5 µm IR
CO2 4.3 µm IR
55
What is the temperature in a VIE?
-150 C
56
What is the pressure in VIE?
7 bar
57
What is the blow off valve pressure in a VIE?
15 bar
58
What is the VIE capacity?
14 days
59
What is the ratio of O2 liquid: gas in the VIE?
1:842 (15C and 1 atm)
60
What is the pipeline pressure of O2?
4.1 bar
61
What is the O2 pipeline made of?
Copper
62
What are O2 cylinders made of?
Molybdenum steel
63
What is the cylinder max pressure?
Working + 70%
64
What size are the scavenging connections of the anaesthetic machine?
30mm
65
What size are the breathing connectors in the anaesthetic machine?
15 + 22 mm
66
What is the max pressure of the APL valve?
60 cmH2O
67
What is the minimum pressure of the APL valve?
0.5cmH20 / 50 Pa
68
What is the reservoir bag capacity? (adult)
2 L
69
What is the max pressure delivered by the reservoir bag?
40cm H2O
70
What flow does the O2 flush deliver?
35 - 75 l/min
71
What pressure is the vaporizer relief valve?
35 kPa
72
What does the O2 alarm do on the anaesthetic machine?
60 dB for 7s at 2 bar
73
What is the voltage of a defibrillator?
5000V DC
74
What is the cardiac impedence of a defibrillator?
50 Ω
75
What is the internal defib energy?
5 - 40J
76
What humidity can an HME filter create?
60-70% RH at 34°C
77
What humidity can a hot water bath create (40°C)?
100% RH and 37°C
78
What speed is a mercury thermometer?
2-3 mins
79
What is the max and min temperatures of a mercury thermometer?
-39 to 270°C
80
What is the speed of a thermocouple thermometer?
0.1 - 15s
81
What are the COSHH limits for halothane?
10 ppm
82
What are the COSHH limits for volatiles (other than halothane)?
50 ppm
83
What are the COSHH limits for nitrous oxide?
100 ppm
84
What is an O2 concentrator composed of?
95% O2
5% Argon
85
What is the suction vacuum?
25 L/min
86
What must a suction perform?
-500 mmHg in 10s
87
What is the central vacuum?
40 L/min
88
What is optimal damping?
0.64 critical
89
What is the flux of MRI?
\<2 tesla
90
What is the size of droplets in the alveoli?
1 µm
91
What is the size of droplets in the trachea?
5 µm
92
What is the voltage of the nerve stimulator?
150V
93
How often does the theatre air change?
15-20 x per hour
94
What is the deadspace of the facemask?
Up to 200ml
95
What is Euler's number?
2.718
96
What is pressure of 1 bar converted to in kPa/ mmHg/ cmH2O?
1 bar = 100kPa = 750 mmHg = 1020 cmH2O = 15 psi
97
What methods of capnography measurement are there?
* IR spectroscopy
* mass spectrometry
* raman scattering
98
What methods of O2 measurement are there?
* pulsed field paramagnetic (fast)
* pauling paramagnetic (slow)
* fuel cell (20-30s)
* clark electrode (20s)
* mass spectrometry
* raman scattering
99
How can volatiles be measured?
* IR spectroscopy
* mass spectrometry
* raman scattering
* piezoelectric
* UV (halothane)
100
Describe the features of an Epidural needle.
* 10.5cm Tuohy needle
* 8cm needle
* 2.5cm hub
* Huber point at 20° to shaft
* 90cm catheter
* 2 or 3 side ports, closed rounded tip
101
What types of spinal needle are there?
* cutting: Quinke & Yale
* atraumatic: Whittacre and Sprotte
* normally 9-10 cm
102
What is the incidence of PDPH after using 20G and 26G needles?
20G 30%
26G 1%
103
What will cause errors in SaO2 measurement?
* CoHb (falsely high)
* MetHb (towards 85%)
* IV dyes
* movement artefact
* nail varnish
* reduced peripheral perfusion
* sats \<70% (extrapolated)
* ambient light
104
What is soda lime made of?
* 80% calcium hydroxide
* 4% sodium hydroxide
* 15% water
* 1% salicylates/dye
105
How much CO2 does 1kg absorb?
250L CO2
106
What can be used for cleaning?
* detergent
* US bath
* low temp steam
107
What are methods of disinfection?
* pasteurization
* alcohol
* chlorhexidine
* hydrogen peroxide (HL)
* gluteraldehyde 2% 20mins (HL)
108
What are methods of sterilization?
* autoclave
* ethylene oxide
* gluteraldehyde 2% 10hrs
* gas plasma
109
What is Avogadro's law?
One mole of gas contains 6 x 1023 atoms and occupies 22.4 L at STP. One mole of solute in 22.4 L solution at 0°C exerts an osmotic pressure of 1 atm.
110
What are the %s for the different standard deviations?
±1 = 68%
±1.96 = 95%
±2 = 95.7%
±3 = 99.7%
111
