Gases
What is Boyle's Law?
At a constant temperature volume of a gas is inversely proportional to pressure
P ∝ 1/V
Define flow?
Amount of fluid moving past a fixed point per unit time (L/min)
Define Temperature?
A measure of the average kinetic energy of the molecules
What is a paramagnetic gas?
A gas that is weakly attracted to an external magnetic field.
What is the equation for Ohms law?
V (voltage) = I (current) x R (resistance)
What is critical temperature?
The threshold above which something behaves as a true gas
A reynolds number above what suggests turbulent flow?
>2000
What is specific heat capacity?
The heat energy required to raise the temperature per unit of mass, measured in joules per kelvin per kilogram
What is Beer's law (ONLY Beer)?
Absorbance is proportional to the concentration of substance in a solution
What is the VF threshold from a microshock?
50-100microAmps
What is the pseudocritical temperature of entenox (both the meaning and the value)?
Temperature at which a gas mixture separates out into its components
-5 C (will accept anywhere between -5 and -7C)
What is Hagen-Poiseuille's equation?
Q = ΔPπr4/8μL
Name the 5 mechanisms of heat loss?
Radiation
Convection
Evapouration
Respiration
Conduction
(Royal college exam room! and conduction)
What are the 2 important wavelengths in a pulse oximeter?
Approx 660 nm (red light)
Approx 940nm (infrared light)
What is meant by common mode rejection ratio?
When an amplifier rejects signals common to both inputs and only amplifies the differential signal
1,5 is the Pin Index for which gas cylinder?
Air
For a peak flowmeter and a pneumotachograph - which is pressure and orifice is constant and which is variable?
Peak flowmeter - constant pressure, variable orifice
Pneumotachograph - variable pressure, constant orifice
What is relative humidity?
The ratio of the actual mass of water vapour in a volume of gas to the mass of water vapour required to saturate that volume of gas at a given temperature.
What does a clarke electrode measure? What are the anode and cathode made of?
Oxygen (in a blood sample)
Platinum cathode
Silver anode
Describe 3 key features of UK Mains electricity supply?
AC
230V
50Hz
Order the following from low to high (don't need specific numbers)
a) oil: gas ratio
b) blood: gas ratio
- Desflurane
- Isoflurane
- Nitrous oxide
- Sevoflurane
Oil: gas
Nitrous Oxide 1.4
Desflurane 26 (19- 29)
Sevoflurane 47 (47-53)
Isoflurane 91 (91-98)
Blood gas
Desflurane 0.4 (0.4-0.45)
Nitrous oxide 0.47 (0.46-0.47)
Sevoflurane 0.68 (0.65 - 0.7)
Isoflurane 1.4
If a venturi mask has an entrainment ratio of 1:4, what % FiO2 would be delivered?
For every 1L of 100%, 4L of 21% = 84
=> 1.84/5 = 0.37 (37%)
A direct linear relationship between temperature and electrical voltage at the junction of 2 dissimilar metals?
Found in a thermocouple
What is the equation that happens at the cathode in a fuel cell?
Cathode = gain of electrons
O2+4e-+2H20 -> 4OH-
Draw 2 pictures:
1) a defibrilator circuit
2) AND what it looks like from the outside when you use it on the ward!
You have to pay to put images in here...