My GS I, GS II, GS IV Answer Booklets

मैं अपनी बची हुई तीनो उत्तर पुस्तिकाएँ भी शेयर कर रहा हूँ। दूसरे पेपर में कुछ जगह सिली मिस्टेक्स भी की हैं। पेपर में पूरा ध्यान प्रश्नो और उत्तर लिखते समय उस पर केंद्रित रहे तो इस प्रकार की गलतियों से बचा जा सकता है।  पहले पेपर में बेसिक चीज़ों का रिवीजन न करने से सही से उत्तर नहीं लिख पाया ,रिवीजन बहुत जरूरी है। अतः इन उत्तरों को आप बस देख लें। मेरे बहुत से साथियों ने पहले पेपर में बहुतअच्छा परफॉर्म किया है और अच्छे अंक प्राप्त किये हैं ,आप इस पेपर के लिए उनके उत्तर देखें। 

उत्तर पुस्तिकाओं के लिंक नीचे शेयर कर रहा हूँ। 

GS II Answer Booklet DS Parmar 138 marks

GS IV Answer Booklet DS Parmar 103 marks

GS I Answer Booklet DS Parmar 85 marks

इन को देखने के लिए बहुत बहुत धन्यवाद। 

My RAS Answer Booklet GS Paper III

काफी समय से  RAS की तैयारी करने वाले मेरे कई  साथी आरटीआई से प्राप्त मेरी उत्तर पुस्तिकाओं की मांग कर  रहे हैं। वैसे मैंने कोई आउट ऑफ़ द वर्ल्ड जाकर उत्तर नहीं लिखे हैं, बस  प्रश्न की मांग को समझते हुए  सरल भाषा में अपने विचार व्यक्त किये हैं।  हो सकता है मेरे कई अन्य साथियो के उत्तर मेरे उत्तरों  से अधिक अच्छे होने के बाद भी उन्हें कम अंक प्राप्त हुए हों।  यह तो उत्तर परीक्षक को उत्तर अच्छे लगना और उस अनुरूप नंबर देने  पर निर्भर है। लक फैक्टर भी जुड़  जाता है। आप अपने विवेक से जो अच्छा लगे ग्रहण करें बाकी छोड़ दें।

link for Answer Booklet.
RAS GS Paper III Answer Booklet DS Parmar 95 marks

RAS IAS UPSC ECE (Electronics and Communication) General Interview Questions

1. Q.1) Ipv4 vs ipv6 (internet protocol version 4 or 6) 

Due to increasing demand of the ip addresses due to mobile internet, internet of things ipv4 (32 bit) address were not sufficient so new ipv6 addresses . 

iss	IPv6
IPv4 addresses are 32 bit length.	IPv6 addresses are 128 bit length.
IPv4 addresses are binary numbers represented in decimals.	IPv6 addresses are binary numbers represented in hexadecimals.
IPSec support is only optional.	Inbuilt IPSec support.
Address Resolution Protocol (ARP) is available to map IPv4 addresses to MAC addresses.	Address Resolution Protocol (ARP) is replaced with a function of Neighbor Discovery Protocol (NDP).
Broadcast messages are available.	Broadcast messages are not available. Instead a link-local scope "All nodes" multicast IPv6 address (FF02::1) is used for broadcast similar functionality.

2. Q.2)  7 layers of Networking model (OSI—open systems interconnections) 

 

Q.3 Communication medium in pre history
 ---fire ,smoke signals, drums,beacons 

5th cen CE-  Pigeon Post 

1838—electrical tlegraph 

1876---telephone 

Q.4 What is a flip-flop? 

A flip-flop is a basic memory element that is made of an assembly of logic gates and is used to store 1-bit of information. 

Q 5. Differentiate semiconductors, conductors and insulators on the basis of band gap. 

The distinction between conductors, insulators and semiconductors is largely concerned with the relative width of the forbidden energy gaps in their energy band structures. There is a wide forbidden gap (more than 5eV) for insulators, narrow forbidden gap (about 1eV) in case of semiconductors and no forbidden gap in case of conductors 

Q6. Why silicon and germanium are the two widely used semiconductor materials? 

Because the energy required to release an electron from their valence band (i.e. to break their covalent bonds ) is very small (1.12eV for Si and 0.72eV for Ge). 

Q7. Describe the difference between P-type and N-type semiconductor materials. 

When a small amount of trivalent impurity (such as boron, gallium, indium or aluminium) is added to a pure semiconductor crystal during crystal growth, the resulting crystal is called a P-type semiconductor. 

When a small amount of pentavalent impurity (such as arsenic, antimony, bismuth or phosphrous) is added to a pure semiconductor crystal during crystal growth, the resulting crystal is called the N-type semiconductor. 

Q.8  What is a rectifier? 

A rectifier is a device which converts alternating current (or voltage) into unidirectional current (or voltage).(AC to DC) 

Q9. Why is it necessary to include voltage stabilizer in a power supply? 

The magnitude of output dc voltage may vary with the variation of either the input ac voltage or the magnitude of load current. So at the output of a rectifier-filter combination a voltage stabilizer is required. 

Q 10. GPRS? 

General Packet Radio Service (GPRS) is a packet oriented mobile data service on the 2G and 3G cellular communication system's global system for mobile communications (GSM). GPRS promises data rates from 56 up to 114 Kbps and continuous connection to the Internet for mobile phone and computer users. . GPRS is based on Global System for Mobile (GSM) communication and complements existing services such circuit-switched cellular phone connections and the Short Message Service (SMS). 

Q.11 Solar Cells ? 

Made of Semiconductor materials(Silicon, Germanium). Sun light is converted to electricity due to photovoltaic effect. 

+ives—renewable energy, use of waste land, open water surfaces, electricity to  remote and rural areas, less carbon foot print 

-ives—poisonous heavy metals used can harm all after entering into food chain,very much water is required to wash the solar cells regularly, heat island is created due to light absorption and radiation.  

Q. 12 Microprocessor V/s Microcontroller 

Microprocessor	Micro Controller
Microprocessor is heart of Computer system.	Micro Controller is a heart of embedded system.
It is just a processor. Memory and I/O components have to be connected externally	Micro controller has external processor along with internal memory and i/O components
Since memory and I/O has to be connected externally, the circuit becomes large.	Since memory and I/O are present internally, the circuit is small.
Cannot be used in compact systems and hence inefficient	Can be used in compact systems and hence it is an efficient technique
Since memory and I/O components are all external, each instruction will need external operation, hence it is relatively slower.	Since components are internal, most of the operations are internal instruction, hence speed is fast.
Mainly used in personal computers	Used mainly in washing machine, MP3 players

Q.13 GSM V/s CDMA 

	CDMA	GSM
Stands for	Code Division Multiple Access	Global System for Mobile communication
Storage Type	Internal Memory	SIM (subscriber identity module) Card
Global market share	25%	75%
Dominance	Dominant standard in the U.S.	Dominant standard worldwide except the U.S.
Data transfer	EVDO/3G/4G/LTE	GPRS/E/3G/4G/LTE
Network	There is one physical channel and a special code for every device in the coverage network. Using this code, the signal of the device is multiplexed, and the same physical channel is used to send the signal.	Every cell has a corresponding network tower, which serves the mobile phones in that cellular area.
Frequency band	Single (850 MHz)	Multiple (850/900/1800/1900 MHz)
Network service	Handset specific	SIM specific. User has option to select handset of his choice.

Q.14 Bluetooth : 

Bluetooth is a wireless technology standard for exchanging data over short distances (using short-wavelength from 2.4 to 2.485 GHz. from fixed and mobile devices, and building personal area networks (PANs). Invented by telecom vendor Ericsson in 1994. The IEEE standardized Bluetooth as IEEE 802.15.1, 

Q.15 Microwave Communication: (eg TV remote) 

the development of radar in World War II provided the technology for practical exploitation of microwave communication. 

Microwaves are widely used for point-to-point communications because their small wavelength allows conveniently-sized antennas to direct them in narrow beams, which can be pointed directly at the receiving antenna. This allows nearby microwave equipment to use the same frequencies without interfering with each other, as lower frequency radio waves do.  

Another advantage is that the high frequency of microwaves gives the microwave band a very large information-carrying capacity; the microwave band has a bandwidth 30 times that of all the rest of the radio spectrum below it.  

A disadvantage is that microwaves are limited to line of sight propagation; they cannot pass around hills or mountains as lower frequency radio waves can. 

Q.16 Radar & Sonar 

Radar (RAdio Detection And Ranging) is an object-detection system that uses radio waves to determine the range, angle, or velocity of objects. It can be used to detect aircraft, ships, spacecraft, guided missiles, motor vehicles, weather formations, and terrain. 

Consists of transmitter, antenna and receiver. 

Sonar (originally an acronym for SOund Navigation And Ranging) is a technique that uses sound propagation (usually underwater, as in submarine navigation) to navigate, communicate with or detect objects on or under the surface of the water, such as other vessels. 

Q.17 ECG 

Electrocardiography (ECG) is the process of recording the electrical activity of the heart over a period of time using electrodes placed on the skin. These electrodes detect the tiny electrical changes on the skin that arise from the heart muscle's electrophysiologic pattern of depolarizing and repolarizing during each heartbeat. It is a very commonly performed cardiology test. 

Q.18 Robotics 

Robotics is the interdisciplinary branch of engineering and science that includes mechanical engineering, electrical engineering, computer science, and others. Robotics deals with the design, construction, operation, and use of robots, as well as computer systems for their control, sensory feedback, and information processing. 

They can be used in Military, Agriculture, Medical, Domestic help. 

Q.19 Fiber optics 

 Works on the principal of Total Internal Reflection.  

Fiber-optic communication is a method of transmitting information from one place to another by sending pulses of light through an optical fiber.  Fiber is preferred over electrical cabling when high bandwidth, long distance, or immunity to electromagnetic interference are required. 

Optical fiber is used by many telecommunications companies to transmit telephone signals, Internet communication, and cable television signals. 

Due to much lower attenuation and interference, optical fiber has large advantages over existing copper wire in long-distance and high-demand applications. However, infrastructure development within cities was relatively difficult and time-consuming, and fiber-optic systems were complex and expensive to install and operate. 

Q. 20 Battery charger processing  

A battery charger, or recharger, is a device used to put energy into a secondary cell or rechargeable battery by forcing an electric current through it. 

Charge and discharge rates are often denoted as C or C-rate, which is a measure of the rate at which a battery is charged or discharged relative to its capacity 

A simple charger works by supplying a constant DC or pulsed DC power source to a battery being charged. A simple charger typically does not alter its output based on charging time or the charge on the battery 

Most mobile phone chargers are not really chargers, only power adapters that provide a power source for the charging circuitry which is almost always contained within the mobile phone. 

Q.21 Lithium Ion Battery 

A lithium-ion battery or Li-ion battery is a type of rechargeable battery in which lithium ions move from the negative electrode to the positive electrode during discharge and back when charging.  

Lithium-ion batteries are common in home electronics. They are one of the most popular types of rechargeable batteries for portable electronics, with a high energy density, tiny memory effect and low self-discharge. LIBs are also growing in popularity for military, battery electric vehicle and aerospace applications. 

Lithium-ion batteries can pose unique safety hazards since they contain a flammable electrolyte and may be kept pressurized. There have been battery-related recalls by some companies, including the 2016 Samsung Galaxy Note 7 recall for battery fires 

Q.22 Display technologies LED V/s LCD ,HDTV , Plasma TV 

  LED V/s LCD

• Screen: LED have thinner screen as compare to LCD.

• Color Quality: LED TVs have excellent color quality as compare to LCD. 

• Life Span: The expected life span of LED TVs is more than thirty years but it is twenty years for LCD.

• Price: While LED TVs are the modern technology so its price is quite high as compare to LCD. 

• Viewing Angles: For LED’s viewing angles is very good and wider contrast to LCD’s. 

• Dynamic Contrast:For LED’s the ratio of dynamic contrast can exceed from 1,000,000:1 whereas this ratio for LCD’s can be exceed 150,000:1.

• Power Consumption:For LED’s less power consumption is there comparative to LCD.

• Environmental Impact:LCD’s have more environmental impact on disposal as compare to LED’s .   
• From the above differences we can say that LED’s are modern technology and shows a better picture as compare to LCD’s.

            Plasma TV 

A plasma display panel (PDP) is a type of flat panel display common to large TV displays 30 inches (76 cm) or larger. They are called "plasma" displays because they use small cells containing electrically chargedionized gases, which are plasmas.

Plasma displays have lost nearly all market share, mostly due to competition from low-cost LCD and more expensive but high-contrast OLED flat-panel displays; manufacturing for the United States retail market ended in 2014, and manufacturing for the Chinese market was expected to end in 2016.

Q.23 CD V/s DVD  

The major difference is the capacity.

Compact Discs (CDs) can store only upto 700 MB while Digital Versatile Discs(DVDs) can store upto 4.7 GB.

Other than that, they differ in read/write speeds. It is the speed at which data is read from or written on the disc. Speeds are generally referred to in ‘x’s, where a 2x CD writes and reads data 2 times faster than a 1x CD.

CDs have a 1x read/write speed of 150 KB/sec whereas DVDs have a 1x speed of approx. 1350 KB/sec. Almost 9 times faster than a CD.

Q.24 Microwave oven? 

A microwave oven (commonly referred to as a microwave) is a kitchen appliance that heats and cooks food by exposing it to electromagnetic radiation in the microwave frequency range. This induces polar molecules in the food to rotate and produce thermal energy in a process known as dielectric heating. Microwave ovens heat foods quickly and efficiently. High water content food item; food is more evenly heated throughout (except in heterogeneous, dense objects) than generally occurs in other cooking techniques.\

Q.25 Electronics in health care : Pacemaker, Glucometer, ECG, Xray , CTscan, sonography, MRI  etc.

Pacemaker: A pacemaker is a medical device which uses electrical impulses, delivered by electrodes contracting the heart muscles, to regulate the beating of the heart.

The primary purpose of a pacemaker is to maintain an adequate heart rate, either because the heart's natural pacemaker is not fast enough, or because there is a block in the heart's electrical conduction system.

 Modern pacemakers are externally programmable and allow a cardiologist to select the optimum pacing modes for individual patients. Some combine a pacemaker and defibrillator in a single implantable device. Others have multiple electrodes stimulating differing positions within the heart to improve synchronisation of the lower chambers (ventricles) of the heart.

Glucometer:
A glucometer is a medical device for determining the approximate concentration of glucose in the blood. It can also be a strip of glucose paper dipped into a substance and measured to the glucose chart. It is a key element of home blood glucose monitoring (HBGM) by people with diabetes mellitus . A small drop of blood, obtained by pricking the skin with a lancet, is placed on a disposable test strip that the meter reads and uses to calculate the blood glucose level. The meter then displays the level in units of mg/dl or mmol/l.

Q. 26 X-Ray:
An X-ray is a common imaging test that’s been used for decades. It can help your doctor view the inside of your body without having to make an incision. This can help them diagnose, monitor, and treat many medical condition 
side effects of X ray procedure:
X-rays use small amounts of radiation to create images of your body. The level of radiation exposure is considered safe for most adults, but not for a developing baby. If you’re pregnant or believe you could be pregnant, tell your doctor before you have an X-ray. They may suggest a different imaging method, such as an MRI.

Q.27 Communication medium in pre history
 ---fire ,smoke signals, drums,beacons 

5th cen CE-  Pigeon Post 

1838—electrical tlegraph 

1876---telephone 

Q.28 what is size of microprocessor? 

what you see in motherboard is not the real size. Because it includes packaging as well as the heat spreader on the top of it. What we design is order of few mm x mm & what we see is order of 2×2 cm. 

some basic question on satellite comm. like  what is geosynchronous satellite and how many are needed for full earth coverage and importance and limitation of satellite comm. and some frequency ranges. 

Q.29 Which is latest  mobile technology?  4G

2)Do I need a new phone for that? if old phone is not 4G unabled then requires new phone.

Q.30 But old age people cannot use hi-fi phones…what do you suggest!? 

I have seen many old people to use them efficiently.functionality is very simple of these phones

they are very much user friendly but its true many old man cant use them bcoz of their fear or due

to no desire to use the new technology.family members specially small children of family

can help the old age people to handle these new tech devices.

Q.31 If I buy a new phone..it will generate e-waste…what about that…how to manage? 

some companies offer now to return the old phones with some value at the time of buying

new phones in exchange offers. or we can give them to some one needy in family or
some home helpers or underprivileged people if we don't want to use them.they will be very happy
to get a phone.

Q.32 People nowadays link mobile tower radiation with cancer..is it true? 

We are exposed to 100 million times more electromagnetic radiation than our grandparents were, and part of the reason is radiation from cell phone towers and microwave antennas.Cell phone towers emit high-frequency radio waves, or microwaves, that can travel as far as 45 miles over level terrain. The closer you are, the greater the danger.

its not proved in any govt survey etc that they cause cancers etc still due to many protests now govt follows some principles like not installing antenna near hospital,schools or on residential buildings etc. still in some research following side effects have found----

 Health Effects

The microwaves from cell phone towers can interfere with your body’s own EMFs, causing a variety of potential health problems, including:

• Headaches
• Memory loss
• Cardiovascular stress
• Low sperm count
• Birth defects
• Cancer

Q.33  Have you heard about 4K technology (Ultra HD) in TV? 

4K Technology also referred as Ultra High Definition (UHD) Technology. The technology refers to the TV or projector’s display resolution. So what is 4K Technology for normal consumers? The current TV resolutions are 720p (1280 x 720 pixels) or 1080p (1920 x 1080 pixels). What 4K technology means is that the current TV, projectors resolution will be multiplied by 4 times. The 4K Technology will offer resolution of 3840 x 2160 pixels.

That amounts to 8 million pixels with each pixel displaying details in their finest form of quality. The 4K technology will deliver fine and smooth video images that unless you are very close to the screen you will not be able to see a pixel structure on the screen.

As the 4K Technology provides much more detail contents, one need a big screen and a projector to watch the movies, pictures in 4K resolution.

Q.34 questions on College final year project can be asked 

Q.35 what is diode 

A diode is an electrical device allowing current to move through it in one direction with far greater ease than in the other. The most common kind of diode in modern circuit design is the semiconductor diode, although other diode technologies exist. Semiconductor diodes are symbolized in schematic diagrams such as Figure below.

The term “diode” is customarily reserved for small signal devices, I ≤ 1 A. The term rectifier is used for power devices, I > 1 A.

Semiconductor diode schematic symbol: Arrows indicate the direction of electron current flow.

When placed in a simple battery-lamp circuit, the diode will either allow or prevent current through the lamp, depending on the polarity of the applied voltage. (Figure below)

Diode operation: (a) Current flow is permitted; the diode is forward biased. (b) Current flow is prohibited; the diode is reversed biased.

When the polarity of the battery is such that electrons are allowed to flow through the diode, the diode is said to be forward-biased. Conversely, when the battery is “backward” and the diode blocks current, the diode is said to be reverse-biased. A diode may be thought of as like a switch: “closed” when forward-biased and “open” when reverse-biased.

Q.36 what is Transistor ? Applications of Transistors? 

A transistor is a three terminal device. Namely,

• Base: This is responsible for activating the transistor.
• Collector: This is the positive lead.
• Emitter: This is the negative lead.

The basic idea behind a transistor is that it lets you control the flow of current through one channel by varying the intensity of a much smaller current that’s flowing through a second channel.

There are two types of transistors in present; they are bipolar junction transistor (BJT), field effect transistors (FET). 

A small current is flowing between the base and the emitter; base terminal can control a larger current flow between the collector and the emitter terminals. For a field-effect transistor, it also has the three terminals, they are gate, source, and drain, and a voltage at the gate can control a current between source and drain. 

Q 37. Diff b/w Analog and Digital Signals ?

Analog Analog signal is a continuous signal which represents physical measurements.Denoted by sine waves,Human voice in air, analog electronic devices.Thermometer Digital Digital signals are discrete time signals generated by digital modulation.Denoted by square waves Computers, CDs, DVDs, and other digital electronic devices like PCs, PDAs

Q 38. What is the frequency used in 4G? 

3G Vs 4G

	3G	4G
Frequency Band	1.8 - 2.5 GHz	2 - 8 GHz
Bandwidth	5-20 MHz	5-20 MHz
Data rate	Up to 2Mbps ( 384 kbps WAN)	Up to 20 Mbps or more
Access	Wideband CDMA	Multi-carrier - CDMA or OFDM(TDMA)

Q.39 Cache memory ? 
Cache memory is a small and very fast temporary storage memory. It is designed to speed up data and instructions transfer speed. It is located inside or close to the CPU chip. It is faster than RAM and the data/instructions that are most recently or most frequently used by CPU are stored in cache.

The data and instructions are retrieved from RAM when CPU uses them for the first time. A copy of that data or instructions is stored in cache. The next time the CPU needs that data or instructions, it first looks in cache. If the required data is found there, it is retrieved from cache memory instead of main memory It speeds up the working of CPU.

Q.40 Tell us about transducers. 
A transducer is an electronic device that converts energy from one form to another. Common examples include microphones, loudspeakers, thermometers, position and pressure sensors
Q what is short circuit? how to prevent it 

Q.41 Universal Gate ?
AND, NOT and OR gates are the basic gates; we can create any logic gate or any Boolean expression by combining them. 
NOR gate and NAND gates have the particular property that any one of them can create any logical Boolean expression if designed in a proper way. Now we will look at the operation of each gate separately as universal gates.
Q .42) Big Data ? 

: Big data deals with ‘data’ that is quite big. 

Lett me explain you this with the help of a real-life example. 

A new flu virus was spreading at a great speed in 2009. This virus was named H1N1. Government feared that is its spread was not contained then it would jeopardize the lives of millions of people. 

However, there was one big problem. One can not stop such a flu from spreading without knowing its current position. 

Government was collecting data by traditional methods which was resulting in a delay of 2 weeks. A delay of 2 weeks is catastrophic in such cases, because by that time the data would be obsolete & no practical steps could be taken to stop it. 

It was during this time, that the engineers at Google, built a method, based on Big Data, that could provide real time statistics about the spread of the virus. And Google, could do this not just on the national level, but also on the regional level and states as well. 

How did Google do it? 

Google gets more than 3 billion search queries per day & saves all of it. 

Google collected data from CDC (Centers for Disease Control & Prevention) on the spread of seasonal flu for the period 2003-2008. Then it compared this data with, the most common, 50 million search terms that Americans type. 

As a result of this Google discovered that there were 45 search terms which when used together could provide real time data about the spread of the virus. 

In short, Google could now tell about the spread of the virus based on what people were typing on Google search engine. 

What took government agencies 2 weeks was now being provided by Google on real time basis. All because of big data . 

What Can We Do With Big Data 

The main purpose of big data is to predict things. 

Public heath, finance & e-commerce are some of the areas where big data is already showing awesome results. 

Future of Big Data 

Big data is the future. It is going to be used enormously both in government & corporate agencies. 

It has its won advantages & disadvantages.----- 

• In the name of security, big data will be used to zero in people. It may be used to punish people even before the crime is committed. 
• Bit data will be used by banks and insurance companies to charge higher loan interests & premiums on certain people. 
• Big data may cause people to see correlations where correlations do not exist – the fooled by randomness phenomena.