Friday, July 30, 2021

Time

Time is very precious to everyone present on the Earth. lets us know how does the time came into existence, somewhere somebody would have taught about this invention.


What is time:

Time in physics and philosophy (time as a physical phenomenon), 
Time in psychology (our sense of passing time), 
Time in mathematics and engineering (the time that we measure and use to regulate our lives). 


History of time :

The measurement of time began with the invention of sundials in ancient Egypt some time prior to 1500 B.C. However, the time the Egyptians measured was not the same as the time today's clocks measure. For the Egyptians, and indeed for a further three millennia, the basic unit of time was the period of daylight. The Egyptians broke the period from sunrise to sunset into twelve equal parts, giving us the forerunner of today's hours. 

The need for a way to measure time independently of the sun eventually gave rise to various devices, most notably sandglasses, waterclocks, and candles. The first two of these utilized the flow of some substance to measure time, the latter the steady fall in the height of the candle.

sundial an instrument showing the time by the shadow of a pointer cast by the sun on to a plate marked with the hours of the day.

Sundial 

The most precise timekeeping device of the ancient world was the water clock.

The hourglass uses the flow of sand to measure the flow of time. They were used in navigation. Ferdinand Magellan used 18 glasses on each ship for his circumnavigation of the globe 

Incense sticks and candles were, and are, commonly used to measure time in temples and churches across the globe

Great advances in accurate time-keeping were made by Galileo Galilei and especially  christiaan huygens with the invention of pendulum-driven clocks along with the invention of the minute hand by Jost Burgi

The most accurate timekeeping devices are atomic clocks.

Atomic clocks use the frequency of electronic transitions  in certain atoms to measure the second.

GPS in coordination with the Network time protocol can be used to synchronize timekeeping systems across the globe.

Measurement of time:

when we travel from one place to another we will calculate the time and speed.
This is way to calculate the time

When we measure the speed of a car, we seem to be measuring speed with something abstract called time; we are actually just comparing a known motion (of the sun) with an unknown motion of the car


History of calendar

Artifacts from the old stone age suggest that the moon was used to reckon time as early as 6,000 years ago.
Lunar calendar were among the first to appear, with years of either 12 or 13 lunar months (either 354 or 384 days). 
solar calendar  is a calendar whose dates indicate the season or almost equivalently the apparent position of the sun relative to the stars.

A lunar calendar is a calendar based on the monthly cycles of the Moon's phases ,In solar calendar annual cycles are based only directly on the solar year.

Living by the clock

Today, we live our lives according to clock. We start our day by an alarm clock, we listen to the radio at a particular time, we travel to and from work at a certain time of day, we attend meetings that start and finish at predetermined times, we eat our meals according to the clock, not simply when we feel hungry, and the clock tells us when to go to a movie, to a concert, to the theater, or to watch our favorite television program. Indeed, not only are most of our daily activities regulated by the clock, they are often ruled down to the precise minute. This way of living is very recent. Not only does it depend on the uniform system of worldwide time measurement, it also requires that each one of us carries on our person a reliable means to keep track of time. 




Sunday, April 25, 2021

Education system

Education plays the most important role in everyone's life. Education does not mean only academic qualifications, it's a form of transfer of knowledge or skill from one generation to another generation.

 
Humans are very intelligent creatures, so they found out a few methods of education from time to time for financial growth and knowledge growth.

History of education system:

Education began in prehistory, education achieved orally and through imitation. Story-telling passes knowledge, values and skills from one generation to the next. 
Schools existed in Egypt at the time of the Middle Kingdom.
 
Plato founded the Academy in Athens.
 
Cicero
Introduction: 2000 years ago, Cicero propagated that education is the best gift we can give to the youth. Education is a dynamic concept with different people interpreting it from their own background or ideals.
 
The idea and practice of universal, compulsory public education developed gradually in Europe, from the early 16th century on into the 19th. 

Education concept during Industrial Era.

Factories altered the educational system, necessitating the need for universal education.
Factory owners required obedient, agreeable workers who would show up on time and do what their mangers told them.

BEFORE THE INDUSTRIAL REVOLUTION
  • Almost all poorer children had no education
  • school wasn't free
  • Majority of the population were poor ,so the country was not as well educated 
  • poor children were going to jobs in factories.
AFTER THE INDUSTRIAL REVOLUTION
  • Schooling was an important part of life
  • Nearly the entire country children were well educated and the country was developing power and strength.
  • Factories helped employees to attend night school to gain knowledge.
  • The country built many libraries.

Education system in India .

The history of education began with teaching of traditional elements such as Indian religions, Indian mathematics, Indian logic at early Hindu and Buddhist centers of learning in Nalanda.

Modern universities were established during British rule in the 19th century.

Development of modern education in India.

The company wanted some educated Indians who could assist them in the administration of the land. Also, they wanted to understand our customs and laws.
Warren Hastings established the Calcutta madrassa in 1781 for teaching of Muslim Law.
In 1791, a Sanskrit college was started in Varanasi by Jonathan Duncan for the study of Hindu Philosophy and laws.
In 1835, it was decided that western science and literature would be imparted to Indians through the medium of English by Lord William Bentincks.
There was a huge demand for clerks and other administration position in company.  
Its cheaper to hire Indians instead of English men.
Bentinck had appointed Thomas Babington Macaulay as the chairman of the general committee of public instruction.
The modern school system was brought to India including the English language, originally by Lord Thomas Babington Macaulay

Interesting facts about education system:

  • The worlds oldest school is The Kings school in Canterbury, England founded in 597 AD.
  • Children in Finland begin schooling only at the age of seven.
  • Schools in Chile have the longest duration of summer Vacations.
  • The ancient education system of India is the pioneer in several areas of study. The number system, place value system, the concept of Zero, trigonometry, algebra, calculus all originated in India.
  • India is the birthplace of Ayurveda. the oldest school of medicine in the world.
  • Nalanda University in India, which was established in 5 AD, is the oldest university in the world. However , the worlds oldest university in continuous operation is the university of Karueein in Morocco founded in 9 AD.




Sunday, January 10, 2021

Laptop repair

Laptop is common device found in everyone house today, so lets us know simple methods if it's not working.

Few precautions to be taken to save data because laptop may Crash anytime.

Backup : backup important data which you have in laptop time to time. we can't predict at what time laptop may crash.

Virus : viruses can attack laptop anytime, so better use antivirus in the system.

Have some knowledge about virus.

Downloaded best antivirus for the system to prevent viruses attack.

Avoid downloading unwanted stuff from unknown site.

Common issues found in Laptop :

  • Laptop crash
  • loading  failure or slowdown Internet connectivity issues.
  • Device compatibility issues.
  • Laptop freezes
  • Blank screen
  • unwanted noise etc.

Why does my laptop not turn on or boot.
  • Connect the power cable. Although it may seem obvious, if your laptop is running on battery power only, connecting the AC adapter may solve the problem
  • Check AC adapter and power port for a bent pin
  • Disconnect from the docking station
  • Remove and reconnect the battery
  • Drain the computer of electricity
Disconnect the AC adapter and remove the battery (if possible)
Hold down the power button for thirty seconds to drain any residual power from the laptop.
Without replacing the battery.
Plug the AC adapter back into the laptop.
  • Bad hardware.

why does my laptop crash:

A computer or system crash is generally an application or hardware component on a computer stops to act properly, and you may sometimes see an error report with the crash, sometimes you may not even see any error codes and your computer keeps crashing.

Most PC or laptop crashes are the result of overheating , hardware faulty, corrupted system or driven corruption, etc.

Few methods to fix PC crashing.

  • Reboot your computer
  • Make sure your CPU works properly
  • Boot in safe mode
  • Update your drivers.
  • Run system file checker.
Basic steps to get rid of Virus.

computer viruses are almost always invisible. without antivirus protection, you may not know you have one. This is why it is vital to install anti-virus protection on all your devices.

If your PC has a virus, few steps to get rid of it.

1 Download and install a virus scanner
2 Disconnect from internet
3 Reboot your computer into safe mode 
  • Turn your computer off and on again
  • when the screen lights ,press F8 to bring up the Advances boot options menu
  • click safe mode with networking
  • Remain disconnect from the internet
4 Delete any temporary files

  • click the windows logo on the right bottom 
  • Type temporary files
  • Choose free up disk space by deleting unnecessary files 
  • Find and select temporary Internet Files in the files to delete Disk cleanup list and click OK 
  • confirm delete files selection
some viruses are programmed to initiate when your computer boots up. Deleting temporary files may delete the virus. 

5 Run a virus scan

6 Delete or quarantine the virus

If a virus is found, it may affect multiple files. select Delete or Quarantine to remove the files and get rid of the virus. Re-scan your computer to check there is no viruses. 

7 Reboot your computer

Now that the viruses is removed, you can reboot your computer. Simply turn it on as you would normally. It no longer needs to be in Safe mode.

8 Change all your passwords

To protect your computer from further attack, change all your passwords in case they were captured by malware.

9 Update your software, browser and operating system

Updating your software, browser and operating system will reduce the risk of flaws in old code being exploited by criminals to install malware on your computer.



Thursday, December 31, 2020

Whatsapp will not work from 2021

WhatsApp is getting a new update that will prevent the messaging app from working on millions of phones from 1 January 2021.

older Android and iPhone devices will not support the latest version of the app.

WhatsApp will not work on few older iPhone and android smartphones. Few may lose access altogether while others may not be able to use a few features on the Facebook-owned platform.

Old smartphone users who have not upgraded to iOS 9 or above or Android 4.0.3 or above will not able to run WhatsApp. It is advised by the makers of the app that the users should update their devices to these versions of their operating system to keep using it. The ones who cant update will either have to buy a new smartphone or look for alternatives to WhatsApp.

Users who are still holding on to the iPhone 4 or lower model will lose access. Similarly, if someone is using a Samsung Galaxy S2, they will not be able to use WhatsApp. 

on iPhone devices system upgrade is easy as they can go into settings followed by general and then tap on software update. This will help them know which version of the OS they are running and whether they can upgrade or not. on the other hand, Android users will find it in the About Phone section in the settings of their smartphone.

other popular phones that will stop running WhatsApp include HTC sensation.

Samsung Google Nexus s, sony Ericsson Xperia Arc.

WhatsApp image

Phones that will lose WhatsApp support from 1 January 2021 include:

  • Samsung Galaxy S2
  • Apple iPhone 1-4
  • HTC Desire
  • LG Optimus Black
  • Motorola Droid Razr
  • Android devices released before 2010

Devices that will need to update to iOS 9 or higher or Android OS 4.0.3 include:

  • Apple iPhone 4S
  • iPhone 5
  • iPhone 5S
  • iPhone 6
  • iPhone 6S
  • Samsung Galaxy S3 and newer
  • Samsung Galaxy Note
  • HTC Sensation
  • HTC Thunderbolt
  • LG Lucid
  • Motorola Droid 4
  • Sony Xperia Pro and newer

Sunday, December 27, 2020

WhatsApp /YouTube/Google maps

 How to broadcast the message in whats-app.

  • Open the whats-app 
  • In the chat screen right side we can find the menu button choose new broadcast
  • choose recipients from your contact list 
  • click done
  • click create.

How to use Google maps without an internet connection.

Losing your Internet connection while traveling can be frustrating especially when your relying on your phone for routes.

Its a good idea to plan ahead for these types of situations by downloading maps for offline use in Google Maps. Once you have downloaded area you will be able to get directions without internet.

there are few limitations 

we cant get walking transit cycling directions while offline.

only driving directions are available.

Steps for offline maps:

  • Download offline maps App from playstore
  • whichever location is needed we can download maps from that APP.
  • we can make use while driving.
How to download MP3 songs from YouTube 

Install YouTube music down-loader.
Download and install freemake YouTube to MP3 Boom. Run the software, follow the instructions Wizard to download music from YouTube.

Find free music for download. Find a song you want to download using the search bar.
YouTube track name, or an album title and hit the enter button on your keyboard.you may preview songs. Before download music from YouTube ,check their correctness and quality.
click the play button before the song.

Download songs from YouTube to iTunes.
click download to download music from YouTube, save full audio tracks as MP3. freemake YouTube music down-loader will automatically save online music in music folder on your computer.
you can change downloadable songs directory in settings tab at the bottom right corner of the program.

Transfer MP3s from YouTube to your phone.
Get free music downloads for your mobile device, if necessary. 






 



Monday, December 14, 2020

how does google maps works

Google maps is used by numerous people on daily basics while traveling as the navigation platform effectively predicts traffic and plots routes for them.

more than million kilometres may driven on daily basics in 220 countries.

How does google maps work.

  • Google maps uses machine learning in combination with various data source including aggregate location data, historical traffic patterns, local government data, and real-time feedback from users, to predict traffic.
  • google maps make use of Dijkstra's algorithm to find the shortest paths between nodes in a graph, which may represent road networks.
  • google maps gets its images from satellite and aerial images in google Earth are taken by cameras on satellites and aircraft, which collect each image at a specific date and time. 
  • Geo-spatial data visualization company and a real-time traffic analyzer, Google Maps was launched in February 2005. 
  • Map maker was added to the american version of google Maps, allowing any viewer to edit and add changes to google maps. This provides Google with local map updates almost in real-time instead of waiting for digital map data companies to release more infrequent updates.
  • Early versions of Google maps relied only on data from traffic sensors, most of which were installed by government transportation agencies or private companies that specialize in compiling traffic data. 
  • using radar, active infrared or laser radar technology, the sensors are able to detect the size and speed of passing vehicles and then wirelessly transmit that information to a server.

Google maps uses an international connection to a GPS navigation system to provide turn by turn voice guided instructions on how to arrive at a given destination The application requires connection to internet data  and normally uses a GPS satellite connections to determine its location.

Data operation team staffed all over the world that plays a role in just about every aspect of map-making from gathering street view images and getting authoritative data sources to correcting the map for inaccuracies and training machine learning models.

Interesting facts about Google maps.

  1. Google maps has over 20 petabytes of data, which is equal to approximately 21 million gigabytes, or around 20500 terabytes.
  2. Google has worked with thousands of business owners in eight countries to bring street view technology inside buildings.
  3. Google maps doesn't use much mobile data at all when navigating. most of google maps data use is incurred when initially searching for the destination.



Friday, December 4, 2020

Pull back toy

Toy is joyfully device found in everyone home where small kids are present.

If we pull wire connected to doll and leave it it will move,simple electronics is used to make beautiful toy.

If we pull wire wheels of dolls will get energy pulling energy converted into mechanical energy and its connected diode it will produce light.

Few things about pull back toy

  • Toy has wind up mechanism inside pull it back and release it will move
  • gears and spring is made used inside the toy
  • Advantage of using this toys are no batteries required.
  • Two gears are made used to move the toy
  • Gear ratio : when large gear rotate once small gear which is connected rotate more than once.
Inside view of toy 

Parts of pull toy

Gears connected to diode

A diode is connected to gear in the motor it will make diode to emit light, mechanical friction is used to generate light. 

A pull back toy is one of the most common toys available on the market. We pull it backwards and then let it go. it travels across almost the entire room before stopping . We pull it back just a few inches, but the distance traveled by the car is 8-12 feet. 

A pull back toy works on the general principle of Newtons Third Law of motion. every action has equal and opposite reaction. The toy car moves forward much further than it was pulled backward. This is possible because of the gears present inside the toy.
When the toy is pulled back, it winds up an internal coil spring by engaging the motor with a clutch. when the toy is released, the spring unwinds and propels the toy forward.

Energy is stored quickly during pullback but gets released slowly during forward motion . The Winding of spring is 10 times faster than when it unwinds. This is achieved with the help of two gear trains present.

Dolly With pull back gears

When we pull the wire and leave it will move forward while emitting light.







Traffic signal

Traffic signal we all know about it especially Bangalore traffic is  biggest issues, but do we know how this traffic signal were invented ,h...