Deck 16: Physics Topics: X-Rays, Ultrasound, Momentum, Force, and Energy

Question 1

Wavelength of x-rays is in range

A)10^-8 to 10 -13 m
B)10 -7 to 10 -14 m
C)10 -10 to 10 -15 m
D)10 2 to 10 9 m

Answer 1

10^-8 to 10 -13 m

Question 2

If fast moving electrons rapidly decelerate, then rays produced are

A)alpha rays
B)beta rays
C)gamma rays
D)x-rays

Answer 2

x-rays

Question 3

As the x-rays pass through matter, it's intensity

A)increases
B)decreases
C)remains constant
D)may increase or decrease depending on the object

Answer 3

decreases

Question 4

X-rays have

A)short wavelength
B)high frequency
C)both A and B
D)longest wavelength

Question 5

Acoustic impedance is defined as

A)ρ⁄c
B)ρc
C)c⁄ρ
D)ρ+c

Question 6

A sound wave which has frequency higher than the upper limit of human hearing is

A)infra sonic
B)ultrasonic
C)supersonic
D)megasonic

Question 7

Fatty tissues have

A)relaxation time of several seconds
B)relaxation time of several hundred nanoseconds
C)intermediate relaxation times
D)relaxation times of several hundred milliseconds

Question 8

Angular frequency of precision is called

A)Lower frequency
B)higher frequency
C)Larmor frequency
D)linear frequency

Question 9

Scattered x-ray beams approach the detector screen

A)perpendicularly
B)parallel
C)anti-parallel
D)at an angle

Question 10

Maximum energy an x-ray photon can have is {{}}

A)e⁄V
B)e
C)eV
D)V

Question 11

Soft x-rays have

A)high energies
B)low energies
C)lowest frequency
D)longest wavelength

Question 12

Intensity of x-rays can be increased by increasing

A)frequency
B)current
C)voltage
D)resistance

Question 13

Bone thickness is equal to {{}}

A)cΔt/2
B)cΔt
C)c/t
D)t/2

Question 14

Hardness of x-ray beam can be increased by increasing

A)voltage
B)current
C)frequency
D)wavelength

Question 15

In x-ray production, the kinetic energy of an electron arriving at anode is

A)100 keV
B)200 keV
C)300 keV
D)400 keV

Question 16

Change in speed of ultrasound causes

A)reflection
B)diffraction
C)refraction
D)image

Question 17

Type of x-rays used to detect break in bone is

A)hard
B)soft
C)both A and B
D)moderate

Question 18

Wavelength of 2.0 MHz ultrasound waves in tissue is

A)7.5 × 10^-4m
B)8 × 10^-5 m
C)8.5 × 10^-6 m
D)9.2 × 10^-3m

Question 19

Intensifier screens reduces the patient's exposure to x-rays by a factor of

A)500-600
B)1000-2000
C)100-500
D)10-100

Question 20

Contrast media consist of elements with

A)lower atomic number
B)higher atomic number
C)metalloids
D)inert gases

Question 21

Thickness of material which decreases intensity of x-ray material to half of original value is

A)quarter thickness
B)half thickness
C)half life
D)2 times of thickness

Question 22

A good x-ray source should produce x-rays of narrow beam and

A)parallel x-rays
B)perpendicular x-rays
C)anti-parallel x-rays
D)anti-perpendicular x-rays

Question 23

Speed of Earth when a rock of mass 60 kg falling towards Earth with speed of 20 m s^-1 is {{}}

A)2.4 × 10^-22 m s^-1
B)3.5 × 10^-33 m s^-1
C)−2.0 × 10^-22 m s^-1
D)−3 × 10³⁴ m s^-1

Question 24

Force exerted by bat on ball if it strikes a ball of mass 0.16 kg initially hits bat with speed of 25 m s^-1 with time impact of 0.003 s is {{}}

A)145 N
B)1333.33 N
C)1456.7 N
D)6543 N

Question 25

Momentum of electron having mass 9.1 × 10^-31 kg and velocity 2.0 ×107 is {{}}

A)1.91 × 10^-23
B)2.34 × 10^-23
C)3.11 × 10^-19
D)7.88 × 10^-34