Exam 2: Sensors and Actuators

arrow
  • Select Tags
search iconSearch Question
  • Select Tags

A consumer TV with 4K resolution has a screen that contains 3840 by 2160 array of pixels.Each RGB LED can shine at 256 intensity levels.The number of bits required to display a complete image equals ______.?

Free
(Essay)
4.8/5
(73)
Correct Answer:
Verified

(3)(8)(3,840)(2,160)=199×106=2.0×108( 3 ) ( 8 ) ( 3,840 ) ( 2,160 ) = 199 \times 10 ^ { 6 } = 2.0 \times 10 ^ { 8 }

An IR autofocus system has emitter and detector apertures separated by 1cm and modeled as pin holes.The light reflected from an object at range r casts a spot that is detected at a displacement of 0.1mm from the detector axis.The detector lies 0.5cm behind the pin hole.The value of r equals _____  (x.x m) \text { (x.x m) }

Free
(Essay)
4.9/5
(75)
Correct Answer:
Verified

f=5×10−3 m, s=10−2 m,x=10−4 m,r/s=f/x→r=sf/x=(10−2 m)(5×10−3 m)/(10−4 m)=5x\mathrm { f } = 5 \times 10 ^ { - 3 } \mathrm {~m} , \mathrm {~s} = 10 ^ { - 2 } \mathrm {~m} , \mathrm { x } = 10 ^ { - 4 } \mathrm {~m} , \mathrm { r } / \mathrm { s } = \mathrm { f } / \mathrm { x } \rightarrow \mathrm { r } = \mathrm { sf } / \mathrm { x } = \left( 10 ^ { - 2 } \mathrm {~m} \right) \left( 5 \times 10 ^ { - 3 } \mathrm {~m} \right) / \left( 10 ^ { - 4 } \mathrm {~m} \right) = 5 \mathrm { x } 10−1 m=0.5 m. 10 ^ { - 1 } \mathrm {~m} = 0.5 \mathrm {~m} \text {. }

Your smartphone has an 8 Megapixel camera  ( 223 pixels) \text { ( } 2 ^ { 23 } \text { pixels) } with each pixel containing red, green,and blue sensors.If each sensor produces 256 levels of intensity, how many bits are required to encode an image?  (Express answer as n.n×10γ ) \text { (Express answer as } n . n \times 10 ^ { \gamma } \text { ) }

Free
(Essay)
4.9/5
(86)
Correct Answer:
Verified

256 levels are encoded with 8 bits, yielding 24 bits/pixel. 24×223=2.4×224=24 \text { bits/pixel. } 24 \times 2 ^ { 23 } = 2.4 \times 2 ^ { 24 } = (2.4)(24)(210)(210)=(2.4)(16)(103)(103)=3.8×107( 2.4 ) \left( 2 ^ { 4 } \right) \left( 2 ^ { 10 } \right) \left( 2 ^ { 10 } \right) = ( 2.4 ) ( 16 ) \left( 10 ^ { 3 } \right) \left( 10 ^ { 3 } \right) = 3.8 \times 10 ^ { 7 }

Finger swipe speed.Your smartphone square touch screen measures 10 cm x 10 cm and implements a 100 x 100 switch array.A horizontal finger swipe must activate at least 25 columns in any particular row within 0.5 seconds.What is the minimum speed (m/s) that your finger must travel to form a valid finger swipe?

(Essay)
4.7/5
(62)

Your smartphone touch screen implements a 100×100100 \times 100 switch array.What is the minimum number of bits that defines the address of each switch assuming separate row and column addresses?

(Essay)
4.8/5
(78)

An air sonar detects the echo TOF from an object to be 10 milliseconds.The object range equals ___ (x.xx)m( x . x x ) m

(Essay)
4.8/5
(77)

Your audio system uses 24 bits to encode audio waveform samples.How many different levels can be encoded using the approximation 210=1032 ^ { 10 } = 10 ^ { 3 }

(Essay)
4.9/5
(74)

A scientific calculator has 5 rows and 9 columns.How many bits required for addressing assuming separate row and column addresses?

(Essay)
4.9/5
(75)

An underwater sonar detects the echo from an object at 100m range.The TOF equals ___ ( x.xxs).

(Essay)
4.8/5
(93)
close modal

Filters

  • Essay(0)
  • Multiple Choice(0)
  • Short Answer(0)
  • True False(0)
  • Matching(0)