HBO CHT EXAM QUESTIONS AND ANSWERS

HBO CHT EXAM QUESTIONS AND ANSWERS
Pressure is defined as? - CORRECT ANSWER✅✅✅The force per unit area acting on a surface in a
direction perpendicular to that surface



Force is defined as? - CORRECT ANSWER✅✅✅An External cause responsible for any change of
physical system.



Acceleration is defined as? - CORRECT ANSWER✅✅✅The rate of change (or time derivative) of
velocity.



Gas is defined as? - CORRECT ANSWER✅✅✅A phase of matter



Solid is defined as? - CORRECT ANSWER✅✅✅A liquid that is at its freezing point.



Plasma is defined as? - CORRECT ANSWER✅✅✅Atoms or molecules that have become ionized.



Liquid is defined as? - CORRECT ANSWER✅✅✅A solid that is at its melting point



In the gas phase, the atoms or molecules basically move? - CORRECT ANSWER✅✅✅Randomly



Liquids change to a gas at? - CORRECT ANSWER✅✅✅Their respective boiling points! Think about
water turning to steam when it boils



When applying pressure to a fluid, the pressure is exerted? - CORRECT ANSWER✅✅✅In all
directions equally. (pascal's law)



Hydraulics is a branch of science and engineering concerned with the mechanical properties of? -
CORRECT ANSWER✅✅✅Liquids! Pneumatic refers to gas fyi

,A mechanical gauge is used when measuring gas pressure in a sealed container. For all common
pressure gauges, the pressure indicated on the gauge is? - CORRECT ANSWER✅✅✅Less than the
absolute pressure (Gauges (and gauge pressures) ignore the ambient (barometric) pressure around us.



Absolute pressure can be defined as? - CORRECT ANSWER✅✅✅The amount of pressure within the
sealed vessel + the amount of pressure outside the sealed vessel.



Gauge pressure? - CORRECT ANSWER✅✅✅The amount of pressure within the sealed vessel only



Ambient pressure? - CORRECT ANSWER✅✅✅The amount of pressure outside of the sealed vessel
only.



Absolute pressure can be defined as? - CORRECT ANSWER✅✅✅Gauge pressure + atmospheric
pressure, Total pressure, True pressure



1 Atm worth of pressure? - CORRECT ANSWER✅✅✅760 mmHg, 14.7 PSI, 33 FSW



Barometric pressure in Denver, CO (elevation 5000 ft) is less than barometric pressure at sea level true
or false? - CORRECT ANSWER✅✅✅True



To Convert from ATA to mmHg - CORRECT ANSWER✅✅✅Multiply by 760



To Convert from ATA to FSW - CORRECT ANSWER✅✅✅Subtract 1, then multiply by 33



To convert from ATA to PSI - CORRECT ANSWER✅✅✅Subtract 1, then multiply by 14.7



To convert from FSW to ATA - CORRECT ANSWER✅✅✅Divide by 33, then add 1



To convert from FSW to ATA - CORRECT ANSWER✅✅✅Add 33, then divide by 33

, To convert from PSI to ATA - CORRECT ANSWER✅✅✅Divide by 14.7, then add 1



To convert from PSI to ATA - CORRECT ANSWER✅✅✅Add 14.7, then divide by 14.7



To convert from mmHg to ATA - CORRECT ANSWER✅✅✅Divide by 760



To convert from PSIG to PSIA - CORRECT ANSWER✅✅✅Add 14.7, PSIG means "pound per square
inch gauge". PSIA means pounds per square ince absolute.



Boyle's law is about the? - CORRECT ANSWER✅✅✅Pressure-volume relationship. Boyle's law says
that with temperature constant, the volume of a gas is inversely proportional to the pressure.



According to Boyle's Law, (assuming the temperature remains constant) when the pressure increases,
the volume? - CORRECT ANSWER✅✅✅Decreases proportionally



When applying Boyle's law to the human body, we worry about air-filled spaces being shrunk ( or
squeezed) when pressure around the body increases. This is known as? - CORRECT
ANSWER✅✅✅Barotrauma



Boyle's law equation? - CORRECT ANSWER✅✅✅P1 x V1=P2 xV2



Charles law is about the? - CORRECT ANSWER✅✅✅Temperature-volume relationship, With
pressure constant, the volume of a gas is directly proportional to the temperature.



According to Charles' law, the volume in a flexible container, like a balloon, will _____ when the
temperature increases. - CORRECT ANSWER✅✅✅Increase proportionally.



According to Charles' law, the volume in a flexible container, like a balloon, will _____ when the volume
increases. - CORRECT ANSWER✅✅✅Increase proportionally.