Computer and Information Technology (Physics) Part-V

Total Questions: 50

31. On which principle digital computer works? [Uttarakhand U.D.A./L.D.A. (Pre) 2007]

Correct Answer: (d) Logical
Solution:

All digital computers rely on binary system of 1 and 0 and on the rules of logic set out in the 1850s by English mathematician George Boole. Just three operations (AND, OR and NOT) can perform all logical functions known as Boolean Logic.

32. If a domain name ends with .edu.us, then it is- [M.P.P.C.S. (Pre) 2008]

Correct Answer: (d) An educational institute in USA
Solution:

.us domain name refers to United States (America) and .edu means education. Therefore .edu.us is the domain name of an American educational institution.

33. In the website of an organization '.com' indicates: [Uttarakhand P.C.S. (Pre) 2010]

Correct Answer: (d) Commercial
Solution:

The .com portion of an organization website is short for commercial. It is a top-level domain (TLD) in the Domain name system of the internet.

34. Which of the following is a valid domain name extension? [M.P.P.C.S. (Pre) 2012]

Correct Answer: (d) All of the above
Solution:

The part after the final dot in the domain name is called top level domain such as www. cnn.com. In this ".com" is the top level domain. Other top level domains are: edu, .gov, .org, .net, .info etc.

35. Consider the following statements and select the correct answer from the codes given below: [M.P.P.C.S. (Pre) 2008]

(1) Proxy server provides TCP/IP address

(2) Proxy server processes clients requests by forwarding the requests to other servers.

Code:

Correct Answer: (b) Only 2 is correct
Solution:

Proxy Server does not provide TCP/IP address, therefore statement I is incorrect. In computer network, a proxy server is a server that acts as an intermediary for requests from clients seeking resources from other servers. Hence, statement 2 is correct.

36. With reference to communication technologies, what is/are the difference/differences between LTE (Long-Term Evolution) and VoLTE (Voice over Long-Term Evolution)? [I.A.S. (Pre) 2019]

1. LTE is commonly marketed as 3G and VoLTE is commonly marketed as advanced 3G.

2. LTE is data-only technology and VoLTE is voice-only technology.

Select the correct answer using the code given below:

Correct Answer: (d) Neither 1 nor 2
Solution:

LTE (Long-Term Evolution) and VoLTE (Voice over Long-Term Evolution), both are high speed mobile communication standards. Both of these communication technologies are used presently in India by various telecom operators under 4G mobile communication systems.

LTE is commonly marketed as 4G and VoLTE is commonly marketed as advanced 4G. LTE may or may not support data usage and voice call together and using data and voice at the same time may affect the quality of the voice call in LTE.

While VoLTE supports data usage and voice call together and using data and voice at the same time in VoLTE does not affect the quality of the voice call

37. With reference to Visible Light Communication (VLC) technology, which of the following statements are correct? [I.A.S. (Pre) 2020]

1. VLC uses electromagnetic spectrum wavelengths 375 to 780 nm.

2. VLC is known as long-range optical wireless communication.

3. VLC can transmit large amounts of data faster than Bluetooth.

4. VLC has no electromagnetic interference.

Select the correct answer using the code given below:

Correct Answer: (c) 1, 3 and 4 only
Solution:

Visible Light Communication (VLC) is the use of visible light as a method of wirelessly transmitting data. It is an affordable method of transmitting data at speed of light. The light (a part of electromagnetic spectrum) wavelengths used in VLC are between 375-780 nanometres.

VLC is a subset of optical wireless communication technologies. The technology uses fluorescent lamps to transmit signals at 10 Kbit/s or LEDs for up to 500 Mbit/s over short distances. Due to the propagation distance of the LEDs, VLC is considered as short-range optical wireless communication.

Light's speed is much greater than the radio waves which makes VLC the fastest means of communication among those commercially available in the market. Bluetooth uses radio waves, and hence VLC can transmit a large amount of data faster than Bluetooth.

VLC has immunity to interference from electromagnetic sources and networks, which affect each other in different radio frequencies, while cause no interference to VLC. Thus, from the above explanation, statement 2 is incorrect while the other three statements are correct.

38. With reference to 'Near Field Communication (NFC) Technology', which of the following statements is/are correct? [I.A.S. (Pre) 2015]

1. It is a contactless communication technology that uses electromagnetic radio fields.

2. NFC is designed for use by devices which can be at a distance of even a metre from each other.

3. NFC can use encryption when sending sensitive information.

Select the correct answer using the code given below.

Correct Answer: (c) 1 and 3 only
Solution:

Near Field Communication abbreviated NFC, is a form of contactless communication between devices like smartphones or tablets. Near field communication utilizes electromagnetic radio fields.

To ensure security, NFC often establishes a secure channel and uses encryption when sending sensitive information such as credit card numbers. NFC enables devices to share information at a distance that is less than 4 centimetre with a maximum communication speed of 424 kbps

39. Consider the following communication technologies: [I.A.S. (Pre) 2022]

1. Closed-circuit Television

2. Radio Frequency Identification

3. Wireless Local Area Network

Which of the above are considered Short-Range devices/technologies?

Correct Answer: (d) 1, 2 and 3
Solution:

Short Range Devices (SRD) are radio devices that offer a low risk of interference with other radio services, usually because of their transmitted power, and hence their range, is low.

The definition 'Short Range Device' may be applied to many different types of wireless equipments, including various forms of: Access control (including door and gate openers), Alarms and movement detectors, Closed-circuit Television (CCTV), Cordless audio devices, including wireless microphones, Wireless Local Area Networks, Remote control, Radio Frequency Identification (RFID), Road Transport Telematics, Telemetry, etc.

40. In the context of digital technologies for entertainment, consider the following statements: [I.A.S. (Pre) 2019]

1. In Augmented Reality (AR), a simulated environment is created and the physical world is completely shut out.

2. In Virtual Reality (VR), images generated from a computer are projected onto real-life objects or surroundings.

3. AR allows individuals to be present in the world and improves the experience using the camera of smart-phone or PC.

4. VR closes the world, and transposes an individual, providing complete immersion experience.

Which of the statements given above is/are correct?

Correct Answer: (b) 3 and 4 only
Solution:

Augmented Reality (AR) overlays virtual objects on the real-world environment. In AR, users see and interact with the real world while digital content is added to it.

AR allows users to be present in the world and improves the experience by adding digital elements to a live view by using the camera of Smartphone of PC.

Virtual Reality (VR) implies a complete immersion experience that shuts out the physical world. VR immerses users in a fully artificial digital environment that is generated by a computer.

Using VR devices such as HTC Vive, Oculus Rift or Google Cardboard, user can be transported into a number of simulated and imagined environments.