past MCQs

Question 1

tables presents main regions of electromagnetic spectrum numbered parts
radiowave, 1, 2, 3, x - rays, 4

Answer 1

1 = infrared
2 = visible
3 = ultraviolet
4 = gamma rays

Question 2

the region of the visible spectrum which has the greatest penetration of human tissue is

Answer 2

red

Question 3

the impulse principle used to reduce RTA accident through

Answer 3

seatbelt
crumple zone
collapsible steering wheel
air bags

Question 4

3 important components of laser system

Answer 4

active medium
excitation mechanism
cavity

Question 5

True of false

the active medium determines the type of the wavelength that can be emitted from the laser devise

Answer 5

true

Question 6

the active medium can be

Answer 6

solid
liquid
gas
plasma

Question 7

laser radiation characterization are

Answer 7

coherent
monochromatic
collimated

Question 8

the type of wavelength can be used in vision correction is

Answer 8

ultraviolet

Question 9

the depth to which laser light penetrates into tissue depends on

Answer 9

wavelength of laser light

Question 10

laser energy may interact with biological tissue in a number of ways. which of the following is the most important type of interaction in terms of laser ability to alter target tissue

Answer 10

absorption

Question 11

which of the following wavelength exhibits the least amount of absorbance into tissue?

a) 250nm
b) 532nm
c) 700nm
d) 1064nm
e) 10600nm

Answer 11

e) 10600nm

Question 12

the following categories of electromagnetic radiation are arranged in the order of increasing frequency

Answer 12

infra red, visible, microwaves, ultraviolet, x rays

Question 13

which of the following is not a vector?
displacement
mass
velocity
momentum
acceleration

Answer 13

mass

Question 14

which of the following is a scalar?
acceleration
energy
force
momentum
velocity

Answer 14

energy

Question 15

which of the following is not a vector?
displacement
time
velocity
force
acceleration

Answer 15

time

Question 16

the frequency of a wave is

Answer 16

the number of waves passing a fixed point in one second

Question 17

low frequencies penetrate

Answer 17

furthest into biological tissue

Question 18

wavelength is defined as

Answer 18

the distance between each repeating element of the wave

Question 19

the ___ of a wave is the number of ___ that pass a fixed point in one second

Answer 19

frequency

cycles

Question 20

the energy of a wave is
directly proportional to
inversely proportional to

Answer 20

directly proportional to its frequency

Question 21

the mechanical property of impulse has important implications for the severity of injuries caused in road traffic accidents. impulse is defined as

Answer 21

change in momentum

Question 22

impact forces in road traffic accidents can be reduced by

Answer 22

increasing interaction time over which the impulse occurs

Question 23

the mechanical advantage of class II lever system can be 
equal to 1 
less than 1
both of the above
none of the above

Answer 23

none of the above

Question 24

laser radiation has the following properties

a) it is produced by stimulated emission of radiation
b) collimated
c) monochromatic
d) coherent
e) all of the above

Answer 24

all of the above

Question 25

clinically useful lasers produce a) mid-infrared radiation b) near infrared radiation c) UV radiation d) visible radiation e) all of the above

Answer 25

e) all of the above

Question 26

in road traffic accident. which of the following is true. a) injuries can be avoided if the impulse is increased b) injuries can be avoided if the interaction time is reduced c) internal injuries often result from the inertia of the internal organs d) active head restraints utilise the impulse principle e) collapsible steering columns are designed primarily to prevent head injuries

Answer 26

c) internal injuries often result from inertia of internal organs

Question 27

impulse principle is described by a) newton's first law of motion b) newtons second law of motion c) both of the above d) none of the above

Answer 27

c) both of the above

Question 28

impact force on the occupant of a vehicle during a traffic accident is reduced by

Answer 28

increase time of impulse

Question 29

impulse is defined as

Answer 29

force x interaction time | change in momentum

Question 30

product of mass and acceleration is

Answer 30

force

Question 31

low frequencies penetrate

Answer 31

furthest into biological tissue

Question 32

``` which one of these has the lowest energy UV gamma rays red light microwaves x - rays ```

Answer 32

microwaves

Question 33

list precautions that must be taken for microshock sensitive patients

Answer 33

electrical equipment should be earthed | patient should NOT be grounded

Question 34

list conditions that consider someone to be microshock sensitive

Answer 34

have artificial pacemaker catheters internally placed conductor

Question 35

stress unit

Answer 35

N/m^2

Question 36

strain unit

Answer 36

ε

Question 37

define compression

Answer 37

intermolecular forces push together, causing the material to deform and thus reducing the volume of the material

Question 38

define tension

Answer 38

causes stretching and elongation of material along axis of load applied

Question 39

shear stress definition

Answer 39

stress acts parallel to surface | deformed by slippage of material

Question 40

The _______ of a force is a measure of the ability of the force to produce a turning effect about an axis.

Answer 40

moment

Question 41

Airbags, collapsible steering columns and padded interiors all use the ___________ Principle to reduce injuries in road traffic collisions

Answer 41

impulse

Question 42

Acceleration is the rate of change of ______________.

Answer 42

velocity

Question 43

If 5 mA is the maximum harmless current and the resistance of dry skin is 100,000 ohms, what is the maximum voltage that will be safe to the body?

Answer 43

500V

Question 44

torque

Answer 44

distance x force

Question 45

skin impedance is ___ proportional to frequency

Answer 45

inversely

Question 46

give value of mechanical advantage of class I lever

Answer 46

less than greater than or equal to 1

Question 47

give value of mechanical advantage of class II lever

Answer 47

greater than 1

Question 48

give value of mechanical advantage of class III lever

Answer 48

lesser than 1

Question 49

elastic deformation

Answer 49

when there is a change in length, but the material can return to its original length.

Question 50

plastic deformation

Answer 50

when the material is beyond its elastic limit and the material can no longer return to its original length

Question 51

The adverse effect of an electric shock to an individual is primarily determined by what factor?

Answer 51

Amount of current flowing through the body