Input Devices in Computer Graphics MCQ Questions and Answers
1. In computer graphics, an input device is used to
A) Display pixels
B) Generate audio signals
C) Provide data and control information to the computer
D) Control the monitor brightness
Answer: C
2. The most common text-based input device is the
A) Light pen
B) Mouse
C) Keyboard
D) Joystick
Answer: C
3. The standard pointing device in most graphical systems is the
A) Trackball
B) Mouse
C) Joystick
D) Touchpad
Answer: B
4. A mouse detects motion using
A) Ultrasonic waves
B) Magnetic coils
C) Optical or mechanical sensors
D) Infrared emitters only
Answer: C
5. The coordinates generated by a mouse movement are interpreted as
A) Absolute screen locations
B) Relative displacement values
C) Random pixel data
D) Color codes
Answer: B
6. A trackball differs from a mouse because
A) It uses a stylus
B) The ball is stationary and the user rotates it
C) It needs no sensors
D) It moves on a flat surface
Answer: B
7. The device used to draw directly on a graphics tablet surface is a
A) Joystick
B) Stylus or puck
C) Light pen
D) Scanner
Answer: B
8. A light pen works by
A) Generating infrared beams
B) Reflecting laser light
C) Detecting light emitted from the CRT screen
D) Electromagnetic induction
Answer: C
9. The light pen senses the beam position using
A) A photodiode at its tip
B) A small magnet
C) A piezo sensor
D) A switch
Answer: A
10. A joystick is primarily an
A) Audio control device
B) Positioning device providing directional input
C) Output display
D) Storage medium
Answer: B
11. The device that converts hand-drawn images into digital form is a
A) Printer
B) Digitizer or graphics tablet
C) Monitor
D) Trackball
Answer: B
12. The “puck” used with a digitizer contains
A) Magnets
B) Gyros
C) One or more sensors to detect tablet signals
D) Phosphors
Answer: C
13. A touch-sensitive screen detects user input through
A) Reflection of light
B) Stylus only
C) Capacitive, resistive, or infrared sensing
D) Ultrasonic reflection
Answer: C
14. A 3-button mouse can generate
A) One binary signal
B) Two analog signals
C) Three independent digital switch signals
D) Four analog voltages
Answer: C
15. The term “picking” in computer graphics means
A) Choosing a color
B) Selecting an object or position using an input device
C) Moving the camera
D) Changing resolution
Answer: B
16. The standard interface for connecting modern input devices is
A) Parallel port
B) USB (Universal Serial Bus)
C) IDE cable
D) SCSI port
Answer: B
17. The process of mapping physical device coordinates to screen coordinates is called
A) Rasterization
B) Coordinate transformation or mapping
C) Quantization
D) Normalization
Answer: B
18. The device that converts visual documents into digital images is a
A) Printer
B) Scanner
C) Monitor
D) Projector
Answer: B
19. Flatbed scanners capture data using
A) CCD (charge-coupled device) sensors
B) Magnetic heads
C) LED diodes only
D) Piezo sensors
Answer: A
20. The device that allows 3-D motion input by detecting hand position is
A) Keyboard
B) Light pen
C) Data glove
D) Trackball
Answer: C
21. The term “degrees of freedom” (DOF) for an input device refers to
A) Number of independent motion parameters it can sense
B) Number of switches
C) Screen refresh rate
D) Resolution in dpi
Answer: A
22. A 2-D positioning device such as a mouse has
A) One DOF
B) Two DOF (X and Y axes)
C) Three DOF
D) Six DOF
Answer: B
23. A 3-D tracker used in virtual-reality environments typically has
A) Two DOF
B) Four DOF
C) Six DOF (three translations + three rotations)
D) Eight DOF
Answer: C
24. Voice input devices work by
A) Reading lips
B) Converting acoustic speech to digital patterns via a microphone
C) Tracking mouth movement
D) Detecting vibrations on screen
Answer: B
25. A data glove senses finger movements using
A) Piezo microphones
B) Optical mirrors
C) Flex or fiber-optic sensors
D) Gyros only
Answer: C
26. The accuracy of a digitizer is measured in
A) Inches
B) Frames per second
C) Lines per inch (LPI) or resolution in dots
D) Hertz
Answer: C
27. The term “locator device” refers to
A) Any input device that identifies a position in 2D or 3D space
B) Audio controller
C) Storage driver
D) Display processor
Answer: A
28. In graphics systems, logical input devices correspond to
A) Display primitives
B) Input functions like locator, valuator, choice, stroke, string
C) Frame buffers
D) Interrupt routines
Answer: B
29. A “valuator device” in graphics provides
A) Text strings
B) Boolean answers
C) Continuous scalar values (e.g., a slider or potentiometer)
D) Colors
Answer: C
30. A “choice device” provides
A) Selection among a finite set of options
B) Numeric input
C) Continuous data
D) Coordinate pairs
Answer: A
31. A “stroke device” returns
A) Integer values
B) Audio tones
C) A sequence of coordinate positions forming a line or curve
D) Color values
Answer: C
32. A “string device” provides
A) Continuous analog data
B) Sequence of characters (e.g., keyboard)
C) Pixel coordinates
D) Switch states
Answer: B
33. A “button device” generates
A) Binary on/off signals for events
B) Floating-point values
C) Strings
D) Coordinates
Answer: A
34. The keyboard can be classified as a
A) String input device
B) Locator device
C) Stroke device
D) Valuator device
Answer: A
35. The mouse is classified primarily as a
A) Locator device
B) String device
C) Stroke device
D) Choice device
Answer: A
36. The light pen belongs to which logical category?
A) String
B) Locator
C) Choice
D) Valuator
Answer: B
37. The joystick is an example of both
A) String + Choice
B) Stroke + Valuator
C) Locator and Valuator device
D) Choice and String device
Answer: C
38. A touchscreen can function as
A) Output device only
B) Both input and output interface
C) Storage unit
D) Audio controller
Answer: B
39. A multi-touch panel detects
A) Single finger contacts
B) Multiple simultaneous touch points
C) Stylus pressure only
D) Joystick rotation
Answer: B
40. The refresh rate of input sampling determines
A) How often device data is read per second (sampling frequency)
B) Screen redraw
C) Phosphor persistence
D) Output voltage
Answer: A
41. The mouse sampling rate is typically around
A) 10 Hz
B) 50 Hz
C) 125–1000 Hz
D) 2000 Hz
Answer: C
42. A spaceball device measures
A) Finger pressure
B) 3-D force and torque inputs for 6 DOF control
C) Screen touches
D) Audio amplitude
Answer: B
43. The term “isotropic sensitivity” in input devices means
A) Equal sensitivity in all directions of motion
B) Sensitivity to temperature
C) Unequal axis response
D) Color variation
Answer: A
44. A head-mounted tracker detects
A) Orientation and position of the user’s head for view control
B) Keyboard input
C) Eye color
D) Speech pitch
Answer: A
45. Eye-tracking devices are used to
A) Measure gaze direction and control cursor or camera view
B) Capture voice
C) Detect temperature
D) Produce sound
Answer: A
46. Magnetic trackers determine position by
A) Infrared reflection
B) Measuring changes in magnetic fields
C) Using lasers
D) Detecting sound waves
Answer: B
47. Optical tracking systems use
A) Magnetic fields
B) Cameras and light markers for motion capture
C) Pressure sensors
D) Ultrasonic emitters
Answer: B
48. Haptic input devices provide
A) Audio feedback
B) Force or tactile feedback to the user
C) Video output
D) Text input
Answer: B
49. The device that converts handwritten characters to text automatically is
A) Joystick
B) Optical character reader (OCR) or digital pen
C) Light pen
D) Spaceball
Answer: B
50. The sensitivity of an input device refers to
A) Minimum detectable change in input signal or position
B) Refresh rate
C) Pixel size
D) Frame rate
Answer: A
51. The precision of an input device refers to
A) Sampling frequency
B) Display resolution
C) Number of distinct values the device can reliably distinguish
D) Device weight
Answer: C
52. The term “tracking” in input systems means
A) Erasing pixels
B) Generating colors
C) Continuous monitoring of device position over time
D) Refreshing the display
Answer: C
53. The input device used for capturing motion of a human actor for animation is
A) Light pen
B) Motion capture system (MoCap)
C) Scanner
D) Joystick
Answer: B
54. The main advantage of a data glove over a mouse is
A) Higher speed
B) Ability to capture 3D hand gestures and finger motion
C) Lower cost
D) Better 2D precision
Answer: B
55. Input devices can be broadly classified as
A) Analog and Digital
B) Text, pointing, and image-input devices
C) Logical and physical
D) Active and passive
Answer: B
56. A digitizer works on the principle of
A) Magnetic induction
B) Capacitive discharge
C) Coordinate encoding via electromagnetic coupling or optical sensors
D) Phosphor emission
Answer: C
57. The advantage of optical mouse over mechanical mouse is
A) Uses ball movement
B) No moving parts and higher accuracy
C) Needs more maintenance
D) Generates noise
Answer: B
58. A graphics tablet differs from a touchscreen because
A) It’s a display
B) It’s an indirect input device
C) It uses CRT beam detection
D) It’s wireless
Answer: B
59. The typical resolution of a high-quality graphics tablet is
A) 50 DPI
B) 150 DPI
C) 1000–5000 LPI (lines per inch)
D) 10,000 DPI
Answer: C
60. Pressure-sensitive styluses can detect
A) X and Y only
B) Pressure applied on the surface for variable stroke thickness
C) Temperature
D) Speed of light
Answer: B
61. Which input device provides six degrees of freedom for 3D modeling?
A) Keyboard
B) Mouse
C) Spaceball or 3D tracker
D) Joystick
Answer: C
62. The process of detecting which object on the screen was chosen by the user is called
A) Highlighting
B) Picking
C) Scaling
D) Blending
Answer: B
63. In OpenGL and GKS graphics systems, input devices are treated as
A) Logical devices
B) Analog modules
C) Display functions
D) Hardware-only interfaces
Answer: A
64. The “event queue” in graphics input handling stores
A) User-generated input events in sequence for processing
B) Display refresh requests
C) Keyboard maps
D) Output colors
Answer: A
65. A valuator input device example is
A) Keyboard
B) Slider or potentiometer
C) Mouse
D) Light pen
Answer: B
66. The stroke device output is used primarily for
A) Text editing
B) Shape or curve input
C) Sound synthesis
D) Color correction
Answer: B
67. The “string input mode” corresponds to
A) Textual input through keyboard
B) Coordinate input
C) Pressure sensing
D) Voice recognition
Answer: A
68. A function key on the keyboard is an example of
A) String device
B) Choice device
C) Stroke device
D) Valuator
Answer: B
69. When a mouse button is pressed, the system receives a
A) Button press event
B) Refresh signal
C) Text string
D) Scan code
Answer: A
70. The physical interface between device electronics and computer I/O ports is called
A) Device driver
B) Buffer
C) Operating system
D) GUI layer
Answer: A
71. Which device is best suited for drawing curves interactively?
A) Keyboard
B) Graphics tablet
C) Microphone
D) Scanner
Answer: B
72. The refresh or update rate of a tracking device affects
A) Color depth
B) Smoothness and accuracy of motion capture
C) Frame buffer size
D) Phosphor persistence
Answer: B
73. Touchscreens in smartphones use mainly
A) Resistive sensors
B) Ultrasonic waves
C) Capacitive sensors
D) Mechanical switches
Answer: C
74. Resistive touchscreens operate by
A) Magnetic induction
B) Detecting pressure between conductive layers
C) Infrared reflection
D) Optical scanning
Answer: B
75. The main advantage of capacitive touchscreens is
A) Multi-touch capability and higher durability
B) Works with any stylus
C) Requires more pressure
D) Needs calibration every use
Answer: A
76. In 3D graphics, “wand” input devices are used for
A) Selecting, pointing, or drawing in 3D space
B) Voice commands
C) Shading pixels
D) Refreshing screens
Answer: A
77. A motion capture suit records
A) Full-body joint movements
B) Only head position
C) Only hand rotation
D) Color intensity
Answer: A
78. Optical motion capture systems require
A) Cameras and reflective markers
B) Magnetic sensors
C) Laser interferometers
D) Accelerometers only
Answer: A
79. In human–computer interaction, the “input bandwidth” measures
A) Amount of information transmitted per second by a device
B) CPU clock speed
C) Refresh rate
D) Screen size
Answer: A
80. A trackpad senses finger motion using
A) Infrared beams
B) Capacitive sensors detecting position changes
C) Magnetic coils
D) Force sensors
Answer: B
81. A barcode scanner uses
A) Ultrasonic detection
B) Laser light reflection from printed patterns
C) Radio waves
D) Magnetic strips
Answer: B
82. OCR (Optical Character Recognition) systems require
A) Scanned image of printed text
B) Vector graphics
C) Keyboard input
D) Audio data
Answer: A
83. The input device used for contour mapping and CAD applications is
A) Keyboard
B) Mouse
C) Digitizer tablet
D) Light pen
Answer: C
84. Which device would be most effective for 3D sculpting software?
A) Keyboard
B) Scanner
C) Haptic stylus or 3D mouse
D) Light pen
Answer: C
85. The key advantage of voice input is
A) Hands-free operation
B) Higher resolution
C) Faster refresh
D) Better color accuracy
Answer: A
86. Gesture recognition devices rely on
A) Magnetic fields
B) Computer vision and depth sensors
C) Audio frequency
D) Laser beams
Answer: B
87. An input device combining camera and infrared projector for depth sensing is
A) Light pen
B) Spaceball
C) Microsoft Kinect or similar depth sensor
D) Scanner
Answer: C
88. An accelerometer measures
A) Angular rotation only
B) Linear acceleration and movement
C) Color intensity
D) Pixel rate
Answer: B
89. A gyroscope measures
A) Translation
B) Angular velocity or rotation
C) Pixel brightness
D) Sound
Answer: B
90. A combined accelerometer + gyroscope sensor gives
A) Color correction
B) Orientation and motion tracking
C) Magnetic field maps
D) Voice input
Answer: B
91. Leap Motion controller works by
A) Measuring magnetism
B) Pressure sensing
C) Using IR cameras to track hand motion in 3D
D) Optical scanning of surfaces
Answer: C
92. The device that directly measures distance to objects using laser pulses is
A) Data glove
B) LIDAR sensor
C) Joystick
D) Puck
Answer: B
93. The refresh frequency of a 3D tracker must be high to
A) Avoid lag and motion jitter in real-time applications
B) Reduce brightness
C) Increase storage
D) Minimize pixel size
Answer: A
94. In CAD, a puck with multiple buttons helps
A) Select menu commands or layers directly
B) Change monitor resolution
C) Adjust brightness
D) Edit text
Answer: A
95. A “multi-modal input system” uses
A) Combination of two or more input types (e.g., voice + gesture)
B) Only one device type
C) A single trackball
D) Laser printer
Answer: A
96. The device used in flight simulators for precise control is
A) Light pen
B) Scanner
C) Joystick or yoke
D) Trackpad
Answer: C
97. A VR controller differs from a mouse because
A) It uses wires
B) It provides 3D spatial input with tracking sensors
C) It has more buttons only
D) It is slower
Answer: B
98. The primary difference between an active and passive stylus is
A) Active stylus has electronics for pressure sensing and signal transmission
B) Passive stylus uses magnets
C) Active stylus has no tip
D) Passive stylus emits sound
Answer: A
99. Input device latency is defined as
A) Time delay between user action and system response
B) Refresh interval
C) Resolution
D) Bandwidth
Answer: A
100. The effectiveness of an input device in computer graphics depends mainly on
A) Accuracy, responsiveness, and ease of control
B) Power consumption
C) Output color
D) Monitor brightness
Answer: A