Case Based MCQ Questions

Computer Science - Class 12
Chapter 10 - Computer Networks

## Center to center distance between various blocks:

 B3 TO B1 50 M B1 TO B2 60 M B2 TO B4 25 M B4 TO B3 170 M B3 TO B2 125 M B1 TO B4 90 M

## Number of computers in each block:

 B1 150 B2 15 B3 15 B4 25

## (D) Bus topology

The star topology network is easy to install, cost effective and failure of any node on the network will not affect the remaining nodes in the network.

So, star topology is best suited for the above given network.

So, the correct answer is (B)

## (C) Telephone line

Checking the options

• (A) Satellite - High speed but very expensive
• (B) Lease line - High speed but expensive
• (C) Telephone line - low speed and cost effective
• (D) Broadband - High speed and cost effective

On comparing all the 4 options, Broadband provides high-speed internet accessibility and is cost-effective.

So, the correct answer is (D)

## (D) Repeater

Checking the options

• (A) Switch/Hub - A switch/hub is a device used to connect multiple computers or communicating devices.
• (B) Modem  - It is a device used for conversion between analog signals and digital bits.
• (C) Telephone - It is a device used for voice communication.
• (D) Repeater -  It is a device used to regenerate signals .

Since switch is used to connect multiple computers.

So, the correct answer is (A)

## (C) Fibre optic

Checking the options

• (A) Micro waves - Not suitable for communication in hilly areas.
• (B) Coaxial cable - Very expensive for long distance communication.
• (C) Fibre optic - Very expensive for long distance communication.
• (D) Radio waves - Cheaper than using wired medium for long distance communication and is suitable for communication in hilly areas.

Radio waves can travel long distances in all directions. It is easy to communicate through radio waves in difficult terrains and it is cheaper than using wired networks for long distance communication.

So, the correct answer is (D)

## (D) BLOCK B3

The server should be installed in the block which has the highest number of computers as it will decrease the cabling cost for most of the computers as well as increase the efficiency of the maximum computers in the network.

Checking the options

• (A) BLOCK B2 - Number of computers is 15
• (B) BLOCK B1 - Number of computers is 150
• (C) BLOCK B4 - Number of computers is 25
• (D) BLOCK B3 - Number of computers is 15

Block B1 has the highest number of computers in the network.

So, the correct answer is (B)

### Transcript

#### Davneet Singh

Davneet Singh has done his B.Tech from Indian Institute of Technology, Kanpur. He has been teaching from the past 14 years. He provides courses for Maths, Science, Social Science, Physics, Chemistry, Computer Science at Teachoo.