Question Discussion & Solution

Arrow moves one, two, three, four, and five sequentially anticlockwise. The arrow head change in a sequence of filled circle → Filled arrow → Open arrow

Next figure is gap of five with open arrow. 

The correct answer is Projector.

Important Points

•  Projector
  • ​A projector is an optical device that projects an image (or moving images) onto a projection screen.
  • There are four main types including;
    • ​DLP: Digital Light Processing, 
    • LCD: Liquid Crystal Display
    • LCOS: Liquid Crystal on Silicon. 
    • Laser projectors 

​Key Points

• Output device
  • An output device is any hardware device used to send data from a computer to another device or user.
  • Some of the output devices are:
    • Visual Display Units (VDU)
    • Monitor, Printer,
    • Graphic Output devices,
    • Plotters, Speakers.

Additional Information

• Mouse
  • A computer mouse is a hand-held pointing device that detects two-dimensional motion relative to a surface. 
• Optical Character Recognition, or OCR
  • ​It is a technology that enables to convert different types of documents, such as scanned paper documents, PDF files or images captured by a digital camera into editable and searchable data.
• Webcam
  • A webcam is a camera that connects to a computer.
  • It captures still pictures or motion video.
  • with the aid of software, can transmit its video on the Internet in real-time. 

The correct answer is 18 Groups and 7 Periods.

• Modern Periodic Table has 18 Groups and 7 Periods.
• It has 118 Elements.
• Each of the tables has a vertical row is called groups. Elements in groups have similar chemical and physical properties because they have the same number of outer electrons.
• Each of the tables has horizontal rows is called periods. During a period, a gradual change in chemical properties occurs from one element to another.
• It was given by Dmitri Mendeleev.
• The Structure of it is like a bird Grid.
• The Modern Periodic table is used to organize all the known elements.
• Advantages of Modern Periodic Table:- 
  •  It is easier to remember the properties of an element if its position in the periodic table is known.
  • It made the study of Chemistry Systematic and Easy.

Modern Periodic Table:-

The correct answer is Operating system.

Key Points

• UBUNTU is an example of an operating system.
• The operating system is a collection of programs that controls the overall operations of the computer.
• Operating systems are of two types namely, Open-source operating systems and Closed source operating systems.
• UBUNTU is free and open-source software.
• Operating systems works as an interface between a user and computer hardware components.
• Examples of operating systems are:
  • Linux
  • Unix
  • DOS
  • Windows
  • Ubuntu
  • Embedded operating system
  • OpenBSD
  • Mac OS

Additional Information

• Malware is a file or code that is designed to damage and destroy computers and computer systems.
  • Viruses, worms, Trojan viruses, spyware are the common examples of malware.
• A web browser is an application used to access and view websites.
  • Google Chrome, Mozilla Firefox, Apple Safari are the common examples of web browsers.

The correct answer is ​Laser Printer.

Important Points

• Hard copy output devices
  • Hard copy output devices are devices that provide output on printed paper or other permanent media that is human readable. 
  • Examples of devices that produce hard copy are printers, plotters.

Key Points

• Laser printers 
  • Laser printers are machines that melt toner powder onto paper to create a print. 
  • Laser printers are more expensive than inkjet printers upfront and use pricier toner cartridges.
  • It is a more economical option in the long run with its overall lower cost per page.
  • Laser printers have faster print speeds.
  • A semiconductor diode laser is currently used in laser printers as the light source.

Additional Information

• Visual Display Terminal
  • The term VDT refers to a type of equipment for visual display, such as computer screens.
• Projector
  • ​A projector or image projector is an optical device that projects an image onto a surface, commonly a projection screen.
• Monitor
  • ​A computer monitor is an output device that displays information in pictorial form.
  • A monitor usually comprises the visual display, circuitry and power supply.