Khans Academy

Q#6: Write the uses of these storage devices: Hard Disk, USB Flash Disk and SD card.  Ans:  • Hard Drive: An internal hard drive is the main storage device in a computer. Hard disks are needed  to install operating systems, programs and additional storage devices, and to save documents . • USB flash drive: It is a very small device to store data which can be travelled with easily.  USB drives are commonly used for  storage, data backup, and transferring files between devices .    • SD Card: An electronic flash memory device used to store digital information and commonly used in mobile electronic devices. An SD card is a removable disk. You can use it  to expand the storage capacity of your smartphone or tablet, allowing you to store more photos, videos, apps, and other files .

Q#5: Discuss impact & non-impact printer with example.  Ans:  Impact Printers: Impact printers are printers which works by creating a direct contact between ink ribbon and paper. These printers are noisy yet popular. Impact printers have mechanical moving parts to conduct printing. Examples: Dot-matrix printers, Daisy-wheel printers, and line printers.  Non-Impact Printers: non-Impact printers don't use any direct contact between ink ribbon and paper. They use laser, xerographic, electrostatic, and chemical or inkjet technology. These printers are less noisy and don't have mechanical moving parts to conduct printing. Examples: Inkjet printers and Laser printers.

Q4: What is the difference between tree and graph data structure? 

Q3: List any three advantages of designing of flow chart.  Ans:  1. Effective Communication : Flowcharts are better way of communicating the logic of the system.  2. Effective Analysis : Using flowchart problem can be analysed more efficiently  3. Proper Documentation : Flowcharts serves as a good program documentation, which is needed for various purpose.

Q#4: Describe artificial intelligence with example.  Ans: Artificial intelligence or AI refers to software technologies that make a robot or computer act and think like a human. Artificial intelligence is a theory and development of computer systems that can perform tasks that normally require human intelligence. Speech recognition, decision-making, visual perception.  There are some everyday examples of artificial intelligence:  1. Google Maps and Ride-Hailing Applications  2. Face Detection and Recognition  3. Text Editors or Auto correct  4. Search and Recommendation Algorithms  5. Digital Assistants  6. Social Media

Q#3: What are the basic operations of a computer system?  Ans: Basic Operations of a Computer System:  A computer is a machine that acts according to the instructions given by the user. A computer performs four basic operations.  1. Input  2. Processing  3. Output  4. Storage

Q#1: Define computer hardware.  Ans: Computer Hardware:  Computer hardware is a collection of all the physical parts or components of a computer. It includes the computer casing, the CPU or central Processing Unit, computer memory, VGA graphics card, sound card and the motherboard.  Q#2: Define Computer Software.  Ans: Computer Software:  Computer software is a computer program that coordinates all the activities and functions of a computer. It also controls all the operations of the computer hardware. It includes operating system, device drivers, utility programs and language translators.

Q2: What are the advantages of developing algorithms.  Ans:  1. It is a step-wise representation of a solution to a given problem, which makes it easy to understand.  2. An algorithm uses a definite procedure.  3. It is not dependent on any programming language, so it is easy to understand for anyone even without programming knowledge.  4. Every step in an algorithm has its own logical sequence so it is easy to debug.  5. By using algorithm, the problem is broken down into smaller pieces or steps hence, it is easier for programmer to convert it into an actual program.

Q1: Describe the steps involved in problem solving.  Ans:  1) Define the problem:  In problem solving process, the first step is defining or identifying the problem. It is the most difficult and the most important of all the steps. During this stage of problem solving, it is important to describe the problem.  2) Generate alternative solutions: For any problem, there are more solutions to it than the one that is thought of first. Postpone the selection of one solution until several problem solving alternative have been proposed.  3) Evaluate and select an alternative:  Many alternative solution to the problem should be generated before final evaluation. A common mistake in problem solving is that alternative are evaluated as they are proposed, sop the first acceptable solution is chosen even if it is not the best solution.  4) Implement and follow up on the solution:  The plan for best solution also include planning on what happens next if somethi...

  Density : The term density of a substance is defined as mass of substance (m) per unit volume (V). It is denoted by Greek letter ρ (rho). The S.I unit for density is kg/m ³ or kgm - ³ Relative Density: The density of substance referred with density of water is called relative density, it has no unit.  

Significant Figure:   The numbers of reliably known digits in a value are known as significant figures. Rules for the Determining Significant Figure: