Universe & ICT Grade -10

Unit -12 
                              Universe 

Unverse: The huge space which contains every things i.e.stars, planets ,satellite, meteorites,  comets etc.  that exist is called the universe .The width of universe is about 100000 light years.

Units of astronomical distance :  There are three widely used units to express the astronomical  distance :
i)Light year: The total distance covered by a ray  of light in the vacuum in one year is called light year .It is also called  big unit which is used to measure the distance in the universe.
Light year =c×t       (Where c = velocity of  light ,t= time taken)
=3×10⁸×60×60×24×365
=9460800 ×10⁸  =9.46×10⁷ ×10⁸m
Therefore ,One light year =9.46×10¹⁵m
ii)Astronomical unit : The distance between the earth and the sun is called astronomical unit .It is also called unit which is used to measure the distance in the solar system .
1 astronomical unit(A.U.)=1.5 ×10¹¹m or 1.5×10⁸km
Solar system: The family of the sun including all planets ,satellites , asteroids , meteors, comets , etc is called solar system .The diameter of solar system is about 10.5 light years .All the bodies in the solar system revolves around the sun. Our solar system lies in the milky way galaxy.

Planet: The heavenly bodies which revolves around the sun in their own orbit is called planet .They do not have their own light .There are 8 planets in our solar system.

Pluto (Dwarf planet): Due to following reason Pluto is not considered as a planet of solar system:
i)The size of Pluto is very small as compared to the average size of other planets.
ii)The  orbit of Pluto is coincided with the orbit of the Neptune .
Now days it is called dwarf planet .
Inner planet or terrestrial planet: The four nearest planet to the sun i.e. Mercury ,Venus ,earth, and Mars are called inner planet .Their structure is similar to the earth so called terrestrial planet . 
 
Outer planet: The satellites which are located outside the orbit of the mars i.e. Jupiter, Saturn, Uranus, and Neptune are called outer planet .Their structure is similar to that of the Jupiter .
Features :i)They are made up from gases.
ii)They have large number of natural satellite .
iii)They have ring system around them i.e. saturn.
 
Asteroid: The tiny planet which revolves around the sun in the space between orbit of mars and Jupiter are called asteroid or small planet or baby planet or minor planet or planetoids .

The diameter of largest asteroid i.e. ceres is about 800km and other small asteroid having diameter  is about 1.6 km to 3.2 km. For example: Ceres, Vesta, Juno, Erars, Pallas,Hygiea etc.
It help to give information about planet and sun .

Satellite: The heavenly bodies which revolves around the planet to their own orbit are called satellite .They are 2 types :
i)Natural satellite: The satellites occurring naturally are called natural satellites .For example :-Mercury and venue have not natural satellite
-Earth have one natural satellite i.e. moon.
ii)Artificial satellite: The man made satellites are called artificial satellites .The artificial satellites are kept at a geo-stationary orbit at a height of 369000km from the earth’s surface.IN SAT(Indian national satellite).

Comet: The heavenly bodies which revolving around the sun in very long elliptical orbit having bright head with long tail are called comet. It is made up from collection gases ,dust particles and ice . For examples:i) Halley comet ii) Temple- tutle iii)Enke iv)Schwasman Wasman  v)Bennett  vi)Shoemaker Levy = collied with Jupiter and collapsed in 1994  A.D.

Differences between Meteors and Meteorites :

Meteors	Meteorites
i-A small pieces of rocks or metal or both which burn and vaporize completely in the atmosphere due to friction between object and atmosphere are called Meteors or shooting star,or falling star. ii-It does not reach to the earth surface. iii-The mass of Meteor is less than that meteorites.	i-A huge piece of rocks or metal or both which does not burn and burn completely in atmosphere due to friction between object and atmosphere is called Meteorite. ii-It reach on the earth surface and form creator on the surface of earth. iii-The mass of Meteorite is more than that of meteor.

Types of Meteorites:  They are 3 types :
i-Stony Meteorite: They have more silicon than that of iron and Magnessium.
ii-Iron Meteorite :They have more iron than that of silicon.
iii-Stony iron meteorite: They have equal amount of iron and silicon.
Constellation: The closed group of star which appear in the form recognizable shape and pattern i.e. human being, animals is called constellation .There are 88 constellation known and named ,out of which 12 constellation are used as sign or zodiac(Rashis) For example :Ursa Major, Ursa Minor, Cepheus, Cassiopeia, Orion(kalpunish); Zodic i.e Leo, etc. Ursa major is a constellation that can be seen with our naked eyes. 

Galaxy: The group of billion of stars ,clusters ,dust and gas all held together by the gravity is called galaxy. There are about 10¹² galaxies in the universe .All the stars of galaxies revolve around the hypothetical center is called galactic center or Nucleus .The diameters of galaxies varies from 1 thousand to 100 thousand light years .for example :Milky way galaxy ,Andromeda galaxy.

Types of galaxy: On the basis of shape there are 3 types galaxies:
i)Spiral galaxy: They are spiral in shape and consist of central part is called nucleus .They are brighter than that of other galaxies .for example: milky way ,Andromeda etc.
ii)Elliptical galaxy: They are elliptical in shape and look like flat elliptical disc For example: NCG 448b,Fonax,Sulptor etc.
iii)Irregular galaxy:They are irregular in shape and less bright than that of spiral galaxy.For example :NCG 6822,IC 559.
Importance of gravitational force in Universe:
1.Shaping the Cosmos: It help to shaping the cosmos because,Gravity controls  the motion of celestial bodies i.e. It keeps planets in orbit around stars, stars in orbit around galaxies, and galaxies in clusters. 
2.Formation of Celestial Bodies: Gravity pulls clouds of gas and dust together, condensing them until they become hot and dense and forming stars planets and other celestial bodies.
3. Giving Us Life: Gravity keeps us grounded and help us to walk, jump, and build our lives here. It's also responsible for Earth's atmosphere, which protects us from harmful radiation and helps regulate temperature. .
4.Cosmology and the Fate(Bhagya) of the Universe: Gravity plays a important role in the study of cosmology, that deals the study of origin, evolution, and fate of the universe. 
Cosmology:  The branch of science that deals the study of  the origin, structure, evolution, and overall properties of the universe is called Cosmology or universe Science .
 
Evolution of the universe according to Big Bang theory:
The Big Bang theory is a scientific explanation of Georges Lemaître, a Belgian cosmologist  for

how the universe began and how it has evolved over time. According to this theory, the universe originated from a hot and dense cosmic egg state around 13.8 billion years ago. Big bang theory can be explained by following facts:

1.The Beginning( Singularity):  At the very beginning, all matter, energy, space, and time were concentrated with in extremely hot and compressed  small space is called"cosmic egg." . It is also imagine as singularty.

2. The Inflation: Then, an event called the Big Bang occurred. due to this event, the universe began to expand and cool down, causing matter and energy to spread out. This period, called cosmic inflation.

3. Cooling and Formation:When the universe expanded, it also became less dense and cooler. After some time, protons, neutrons, and electrons formed, that leading to the formation of hydrogen and helium atoms.
 Over millions of years, these atoms began to come together due to gravity, forming stars and galaxies. 

The galaxies, including our own Milky Way, continued to move away from each other as the universe expanded. This expansion is still ongoing today.

4.Evidence:  We have strong evidence supporting it, like the cosmic microwave background radiation, the abundance of light elements in the universe, and the large-scale structure of the cosmos.
 
 Hobble’s study Regarding the Velocity of the Heavenly Bodies:
Edwin Hubble an American astronomer, observed that galaxies were not stationary but were moving away from us,  and the light emitted by galaxies, specifically focusing on a phenomenon called "redshift."  Hubble's law states that the recessional velocity of a galaxy is directly proportional to its distance from us.
Mathematically, it can be expressed as
v = H₀ d
where v is the recessional velocity, d is the distance to the galaxy, and H₀ is the Hubble constant.

The Hubble constant represents the rate at which the universe is expanding. It help to show the relationship between the recessional velocity and distance and allows scientists to estimate the age of the universe.
Future of the universe:
 There are some major  theories and possibilities  about the future of the universe:
1.Expansion and Dark Energy(विस्तार र अँध्यारो ऊर्जा:): According to this scenario(परिदृश्य),The universe is currently undergoing a period of accelerated expansion, driven by a mysterious force called dark energy. It is believed that this expansion will continue indefinitely, causing galaxies are separated from each other over vast timescales.
2.Heat Death: According to this scenario , Due the universe expands, the average temperature will decreases, so all stars will eventually burn out (Jalera nast hunu), and the universe will become a cold, dark, and lifeless place.
3.Big Crunch: According to this scenario ,If the amount of matter in the universe is large enough and the expansion is not counteracted(Jitna) by dark energy, then gravity could the stop the expansion, causing the universe to collapse in on itself. This would result in a dense and hot state, and leading to another Big Bang and the birth of a new universe.
.
Types of Universe :According to scientist there are 3 possible types of the universe :

1.Open Universe: According to this model of universe our universe is constantly expanding, by a mysterious force called dark energy, which counteracts(jitnu) the pull of gravity. The open universe model assumes that the overall density of the universe is too low to stop this expansion through gravity, and the universe will continue to stretch forever. 

2.Flat universe: According to this model of universe our universe expand indefinitely but at a decelerating rate due to the total density of matter, both the visible matter and dark matter, is balanced with the density of dark energy. The Flat universe model assumes that the total density of matter,  both visible matter and dark matter, is  balanced with the energy density of dark energy. This balance allows the universe to expand indefinitely but at a decelerating rate.

3.Closed universe: According to this model of universe our universe stop expanding and then collapse back in on itself in a "Big Crunch" Due to the overall density of the universe is too enough to  stop this expansion through gravity. The Closed universe model assumes that the overall density of the universe is too enough against density of dark energy that stop expanding and then collapse back in on itself in a "Big Crunch."

Unit -13   
Information and Communication  Technology
Signal :An electromagnetetic or electrical current that is used for carrying data from one source or network or device to another source or network or device  is called  signal .
Types of signals :

1.Analog Signal :  A continuous electrical signal having continuous variable value with time is known as Analog signal .These signal work with physical value and natural phenomena such as sound received by mic,sound played by speaker, human voice,  temperature readings, and signals from various sensors such as microphones, thermometers, or pressure sensors, earthquake,volcanoes, wind speed, temperature .They are represented by sine wave but can not be represented by binary number 0 and one .ADC(Analog digital coverter) convert digital signals into analogue signals . Analogue signal's amplitude (strength) is directly proportional to the value of the original information. i.e. Sound waves from a microphone. The devices of analogue signal are little complicated and hard to read accurately but more accurate than digital signal .

In an analogue signal, the information is encoded as varying voltage, current . 

 Analogue signals are used in various applications such as telecommunications, audio and video processing, control systems, Analogue watch(i.e. needle watch) and scientific measurements.

2.Digital Signal :

 A non continuous electrical signal having discontinuous discrete  values with time is called digital signal.for example music file in you tube.They are represent by square wave and by binary number 0 and 1.DAC(digital analogue converter) coverts analogue signals into digital signal.  For example: Music play by computer

They are processed and transmitted using digital devices such as computers, microcontrollers, digital circuits, and digital communication protocols and more easy to use.For example: i)Computer data i.e.text,music,image video  ii)Internate data i.e. websites   iii)Mobile signal i.e.audio video,text

Types of communication :On the basis of signal there are two types of communication :
1)Analogue communication :The communication in which data are transmitted between transmitter and receiver by help of analogue signal is called Analogue communication. It is affected by external factors and coding not possible in this communication.
2.)Digital communication :The communication in which data are transmitted between transmitter and receiver by converting analogue into digital and digital into analogue as output is called Digital communication. It is not affected by external factors and coding  possible in this communication.
 
Some unit of Digital Signal : These units indicate the amount of information or storage capacity of a digital signal.

1.Bit (binary digit): The fundamental or smallest unit of information in digital signals is called Bit It is denoted by either 0 or 1.
1 or 0 =1Bit
2.Byte: A group of 8 bits, commonly used to represent characters or small numbers.
   8 bit= 1 byte / 1 character
4 bit = 1 Nibble 
3. 1024 bytes =Kilobyte (KB). 
4. 1024 kilobytes =Megabyte (MB) .
5.1024 megabytes =Gigabyte (GB) .
6.1024 gigabytes =Terabyte (TB) .
7.1024 terabytes = Petabyte (PB) .
8.1024 petabytes =Exabyte (EB) .
9.1024 exabytes = Zettabyte (ZB): .
10.1024 zettabytes = Yottabyte (YB): .

 Unit of transmission of digital signals:
1.Baud: The rate at which symbols are transmitted in a digital signal, measured in symbols per second (symbol/s).
2.Bit rate: The number of bits transmitted per second (bit/s).
3.Kilobit per second (kbps): 1000 bits per second.
4.Megabit per second (Mbps): 1000 kilobits per second.
5.Gigabit per second (Gbps): 1000 megabits per second.

Signal transmission :The process of transmission of Signals (information) from one point to another using by transmission medium or communication channel is called signal transmission.

They are two types :
1.Transmission of analogue signal:
The process of transmission of sending a continuous wave form or signal through a communication channel from a sender to a receiver is called Transmission of analogue signal . The original analogue signal is converted into electrical or electromagnetic waves that can propagate through a medium such as a wire, fiber optic cable, or the air (in the case of wireless communication) in the form of voltage, current, sound waves, or any other physical quantity that can be measured and represented as a continuous waveform.Examples:

1.Voice Communication: Traditional telephone systems transmit voice signals as analogue signals. 
2.Radio Broadcasting: FM (Frequency Modulation) and AM (Amplitude Modulation) radio broadcasts transmit audio signals using analogue modulation techniques. 

2. Transmission of Digital signal or Digital Communication: The process of transmission of sending information encoded as discrete, binary values (0s and 1s) from one point to another is called transmission of Digital signal . These signals are  transmitted as electrical pulses or light pulses through cables radio waves, microwaves, and infrared light .In this communication the analogue signal is first converted into digital and converted again into analogue from the output device.   Examples: Sending text messages or emails over the internet ,Streaming music or video online, Downloading files, Making calls on a mobile phone, Transferring data between computers. There are 2 types of transmission of digital signals:
i)Baseband transmission :The process of transmission of digital signals through a communication channel without changing it into analogue signals is called Baseband transmission. This types of transmission covers short distance and a single cable can carry only one signal at a time. so It is used in local area network(LAN). It is bidirectional transmission .  For example transmission of data between two  computer by help of cable.
ii)Broadband transmission: The process of transmission of digital signals through a communication channel by changing it into analogue signals is called Broadband transmission. This types of transmission covers long distance and a signal cable can carry multiple signals at a time so it is used in wide area network(WAN). It is unidirectional transmission ,Cable TV. For example :Transmission data between different devices of internet .It is also called high speed of internet.
 
Advantages of digital transmission :
1.Reliability: Digital signals are less susceptible(संवेदनशील) due to noise interference(ध्वनि हस्तक्षेप) during transmission than analogue signals..
2.Clarity: Digital signals  ensures that the information being transmitted is clear and error-free.
3.Security: Digital data is important for transmitting sensitive information such as financial data or medical records.
4.Efficiency: Digital data can be compressed to reduce its size, which makes it more efficient to transmit. large files such as videos or images.
5.Cost-effectiveness: Digital transmission systems are cheaper to transmit and store digital data.
6.Versatility: Digital transmission can be used to transmit a wide variety of data, including voice, data, and video as versatile tool.
7.Scalability: Digital transmission systems can be easily scaled to meet the needs of a growing network.
8.Integration: Digital data can be easily integrated with other digital systems.
9.Error correction: Digital transmission systems can include error correction mechanisms that can detect and correct errors that occur during transmission.
10. Accessibility: Digital transmission has made it possible to access information and services from anywhere in the world.
 
 Positive impacts of digital technology in daily Life::
1.Communication: It help to easily connect and communicate with each other through various platforms like social media, messaging apps, and video calls.
2.Education: It help in education by providing online learning platforms, educational apps, and resources,.
3.Information access(पहुँच): It help to  provides instant access to a vast amount of information, research various topics, and expand their knowledge.
4.Productivity: It help to provide productivity apps, project management software, and collaboration platforms help individuals and businesses increase efficiency.
5.Healthcare: It help in healthcare through telemedicine, remote monitoring, electronic health records, and medical apps, improving accessibility and quality of care.
6.Entertainment: It help in various forms of entertainment such as online gaming, virtual reality, and, providing enjoyable experiences.
7.Financial services: It help for Online banking, mobile payment systems, and digital wallets .
8.Social activism: It help to provide  voice of communities and facilitate social activism,  to raise awareness, organize movements for change.
9.Environmental impact: It help to contribute positively to the environment by reducing paper waste through digital documents, promoting remote work and enabling smart energy management systems.
 
Negative Impacts of digitals technology in daily life :
1.Cybersecurity threats: such as hacking, identity theft, and data breaches, leading to financial and personal harm.
2.Addiction:, such as social media, gaming, , can lead to addiction, affecting mental health, productivity, and relationships.
3.Privacy concerns: It help to collects and stores personal data, concerns about privacy and misuse of personal information.
4.Cyberbullying: It is used for cyberbullying, harassment, and spreading harmful content, causing emotional distress and psychological harm to individuals.
5.Disinformation: It help to the spread of false information and misinformation, leading to confusion, among individuals and communities.
6.Social isolation: It help to contribute to social isolation, reducing face-to-face interactions and genuine human connections.
7.Health issues: It help to contribute to physical health problems such as eye strain, musculoskeletal issues, and obesity(मोटोपना).

Components of digital communications system:
i.)Source :The source that help to produce analogue signals for  transmission .For example : Sound wave.
ii)Input Transducer: The input transducer receives analogue signals and change them into electrical signals For example: Microphone convert sound into electricity.
iii.)Encoder: The encoder compresses data to minimum bit number that help for easy transmission of signals.
iv)Modulator: The modulator  modulates(change) the signals and converts into analogue signal and pass into the channel.After converting into analogue signals ,modulator gives direction to pass into medium or channel. 
v) Channel: Channel is a path in which signals transfer from transmitter to receiver. It provides a pathway for the transmission of signals or data. For example: Wired Channel, Wireless ,Optical Channel, Virtual Channel.
vi)Demodulator: Demodulator demodulates the received signals .It removes the additional information .It is also called the first stage for receiving signal. .
vii)Decoder: The decoder changes demodulated analogue signals into digital signals. it helps to reduce error in output signals .
viii)Out put transducer : Out put transducer change decoded or electrical signals into original physical information. For example: Loudspeaker convert electrical signal into Sound.
ix)Output signal: The signal  that is produced  by a device, as a result of processing of input signals is called output signal .It is exactly original physical information. 

Components of Analog communications system:
1.Source :The source that help to produce analogue signals for  transmission .For example : Sound wave.
2.Input transducer: The input transducer(ADC) receives analogue signals and change them into electrical signals For example: Microphone convert sound into electricity.
iii)Modulator: The modulator  modulates(change) the signals and converts into analogue signal and pass into the channel.After converting into analogue signals ,modulator gives direction to pass into medium or channel.
iv) Channel: Channel is a path in which signals transfer from transmitter to receiver. It provides a pathway for the transmission of signals or data. For example: Wired Channel, Wireless ,
v)Demodulator: Demodulator demodulates the received signals .It removes the additional information .It is also called the first stage for receiving signal.
vi)Out put transducer : Out put transducer change  electrical signals into original physical information. For example: Loudspeaker convert electrical signal into Sound.
vii)Output signal: The signal  that is produced  by a device, as a result of processing of input signals is called output signal .It is exactly original physical information

Digital citizenship:The responsible and respectful use of technology to navigate the online world is known as Digital citizenship. The person that use the technology to navigate the online world  is called Netizen. It consist of following Facts . i. Respect .ii. Responsibility iii. Literacy iv. Safety v. Privacy vi .Rights and Responsibilities.

 
Characteristics of good netizen:The person that use the technology to navigate the online world  is called Netizen.A good netizen consist of following features:
A.Rights and Responsibilities.
i.Think before you post: such as Avoid cyberbullying, harassment, and spreading negativity.
ii.Be mindful of privacy: Respect the privacy of others and don't share personal information without their consent.
iii.Be polite and courteous: Treat others online with the same respect you would in person.
iv.Fact-check information: Don't blindly believe everything you see online.
v.Be aware of bias(पूर्वाग्रह): Recognize that information online can be biased
vi.Fight misinformation: If you encounter false information, politely challenge it
B.Safe and Secure:
i.Protect your privacy
ii.Practice good password hygiene: Use strong, unique passwords and be mindful of where you enter them.
iii.Be cyber-aware: such as  online threats like malware.

Online(Digital) Reputation: The perception(Concept), impression, or evaluation of an individual, organization  formed by others based on their online presence, activities, and interactions is known as Online reputation .. It is the collective opinion that develops as a result of various online sources, including social media, online reviews, forums, news articles, and other digital platforms.
An online reputation is shaped by the content and information available about a person online, to their social media profiles, website, blog posts, comments, and mentions across various online platforms
it can impact personal and professional opportunities, relationships, and perceptions.
A positive online reputation can enhance credibility, trust, and opportunities, while a negative reputation can lead to mistrust, damage to personal or professional relationships, and missed opportunities.

Factors affecting online reputation:

1.Technological problem:If company server has technical problem whether they are financial or instructional problem ,it can hurt their reputation.

2.Spread of misinformation:Speed of misinformation about the individual or company through internet can damage a reputation.

3.Bad review:Bad review always  act as repellent for the customer towards the brand.

4.Security breaches :An organization loss its reputation if it is unable to protect or secure its digital data from being hacked and manipulated.

5.Social media:The negative comments are rapidly spread through social media. They affect reputation of an individual or an organization.
 
Digital wellbeing: The healthy and balanced relationship between your real life and technology is called Digital welling .For example :The healthy and balanced use of technology consist of following facts such   Balance, Awareness, Boundaries, Positive Tech Habits etc.
 Cautions digital wellbeing :
1.Excessive Screen Time: Set limits on screen time and take regular breaks to engage in physical activity and rest your eyes.
2.Social Media Comparison: Practice self-compassion and focus on your own journey rather than comparing yourself to others.
3.Cyberbullying and Online Harassment: Report and block any instances of harassment and seek support if you are a victim.
4.Privacy and Data Security: Regularly review privacy settings on social media platforms and other online services to ensure you have control over what is shared.
5.Digital Exhaustion and Overwhelm(थकान र भारी)

: Take regular digital detoxes, set boundaries around technology use, and engage in activities that promote relaxation and stress reduction.
6.Online Scams(घोटाला)and Phishing: Develop critical thinking skills and verify information from reliable sources before believing or sharing it.

7.Digital Addiction: Be mindful of your digital habits and seek support if you find it difficult to control your technology use.
 
Making  audio and audio-video materials :The audio and audio- video materials can be prepared by using  video editing software such as wonder share Filmora, Cap cut, Microsoft Clipchamp etc.
 Method of recording audio or voice in smart phone:We can follow the following steps to record and save your audio file:

Step:1 Locate or download a voice recorder application on your phone and click on open.

Step:2 Press the record button to begin recording .

Step:3 Press the stop button to stop recording.

Step :4 Click on save button a window with few details open up.

Step :5 Type the file name and click on save button.

Method of recording video in smart phone:We can follow the following steps to record and save your video file:

Step:1 Open camera of your device .

Step:2 Press the record button on your screen to start the video recording .

Step:3 Press stop button to end the video recording .

Step:4 Some of the device save the video automatically while other ask your permission .So you may press  on save button in such case .To find your recorded video search either a video application  or a application  or gallery application. 

Method of merging video online in computer:Several applications are available in the internet that can be used for merging or joining the video online such as Video editor ,VLC media player,Cap cut,Cam studio,Wonder share etc. We can follow the following steps to to merge the video online and save your video file: 

Step:1 Import the source video by clicking import button or you may drag the video to the appropriated area.

Step:2 Add the imported file to the track by choosing the Add to project Option or you may drag and the videos to the trak.

Step :3 Click on Export to merge the video. 

Video Editing : The process of manipulating(हेरफेर) and rearranging video footage, audio, and other elements to create a final, polished video product  is known as video Editing. It consist of, selecting and trimming video clips, video cutting, video joining arranging them in a desired order, applying transitions and effects, adjusting color and audio levels, and incorporating other visual and audio elements for the presentation.
Video editing is commonly performed using specialized software, often referred to as video editing software such as wonder share Filmora, Cap cut, Microsoft Clipchamp etc..