This simple experiment will show the power of frictional force when several sheets of paper are overlapped.
Materials needed.
2 notes or exercise books with approximately the same number of pages.
Procedure
On a table or flat surface, open the 2 books to their last pages and overlap their back covers.
Then take the next pages and overlap each one. Continue doing this until you reach their front covers.
Tell a friend to hold the binding of one book, and you hold the other one.
Try to pull the notebooks apart this way and see what happens.
The books should be very difficult to pull apart.
Explanation
The surface of paper appears smooth to the naked eye. But when viewed under a microscope it has a rough surface. When 2 or more paper surfaces come in contact, the surfaces interlock due to frictional forces. The frictional forces existing between the paper surfaces makes it difficult to pull the notebooks apart.
Manchester City have won the English Premier League Title on the final day of the 2021/2022 season.
Mamchester City Players Celebrating goal Scored
They came from 2 goals down to beat Aston Villa by 3-2. Manchester City finished top of the table with 93 points.
Liverpool beat Wolves 3-1 to finish in second place with 92 points. No quadruple for them this season.
Chelsea came third with a distant 74 points while Tottenham finished 4th with 71 points.
Burnley, Watford and Norwich finished 18th(35 points), 19th (23 points) and 20th(22 points).
Manchester City, Liverpool, Chelsea and Tottenham qualify for the Champions League.
Arsenal and Manchester United qualify for Europa League.
WestHam qualify for Conference League .
Burnley, Watford and Norwich are relegated.
English Premier League (Club Stats)
Manchester City scored the highest goals of the season: 99 goals followed by Liverpool with 94 goals, Chelsea came third with 76 goals scored.
Best defence goes to Manchester City, Liverpool coming second and Chelsea, coming a distant third. City and Liverpool both conceded 26 goals this season and Chelsea conceded 33 goals.
Norwich City is the team with the worst defence shipping a total of 84 goals conceded.
English Premier League (Player Stats.)
Heung Min Son of Tottenham is the highest goal scorer this season with 23 goals, followed by Salah of Liverpool with 22 goals and third is Christiano Ronaldo with 18 goals.
Salah top the assist chart with 13 assists, followed by Alexander with 12 assists, both of Liverpool. Barnes of Leicester City is third with 11 assists.
Final Standings: English Premier League
English Premier League Table: Final Standings . Source: BBC sports.
This short article describes how to use Adobe illustrator to change a raster image to a vector image
Open illustrator
And go to file then click place, next, select the picture you want to convert to vector image and then import into illustrator.
Next, click on Window, then Image trace.
In the image trace box, click on the check box next to Preview. This will enable you to see changes made when the image is traced.
Set Preset to High Fidelity Photo
Mode to Color
Palette to Full Tone
Finally select the image and click on Expand to convert the traced image to paths.
If successful, You will see that in the layers panel, each element comprising the picture has been placed in its own layer and grouped making the image fully editable.
Have some text already typed into a text box With segoe print font.
Get a picture of a hand holding a pen and scale it appropriately under the text.
Go to animation then animation pane.
select all the text and click the fade animation.
Set the duration to 0.5.
In the animation pane window, go to the handwriting animation event.
Click the down arrow next to the animation event and click effect options. Set Animate text to by letter.
Directly under Animate text, Set to 100% delay between letters then click ok to close the box. Test the animation, the letters should appear one by one.
Now to animating the hand holding a pen.
Multiply the number of letters in the text by the duration of the last animation which is 0.5.
This value will be the duration of the hand animation.
Go to the animation window, then look for and click motion paths, then custom paths.
The cursor will change to a crosshair, zoom into the text, then with your mouse or pen, trace the path of the text from start to finish as if you were writing it.
The path will be recorded. Double click to preview the animation. Change the duration to the value previously calculated for the hand animation.
In the animation pane window click the down arrow next to the hand animation.
Then click effect options and set smooth start and smooth end to 0 sec. then click ok
Test the animation to see changes.
Now the text and hand animation has been made.
Try to position the hand holding pen picture under the text as realistically as possible.
Set the hand holding pen picture to bring to front.
Set the hand holding pen animation to start: with previous above the animation pane.
Test the animation. The hand holding pen should be writing the text smoothly now.
To make the hand holding pen go away after the animation you need an exit animation.
Go to add animation and click fly out
Set the fly out animation to Start: after previous
A series connection of batteries is achieved when the negative terminal of one battery cell is connected to the positive terminal of another battery cell. 2 or more battery cells can be connected this way. An example of application of series connection of batteries is in the use of a touch light. Typically 2 batteries are connected in series for the touch light to come on.
In a series connection of batteries, voltage increases while current stays constant.
For example let’s say 2 battery cells are rated 1.5 V and 1A each and the cells are connected in series. Then the combined voltage for the series connection becomes 1.5V + 1.5V = 3V but the current remains 1A.
Using the previous cell ratings, an electrical appliance that needs 6 volts to come on will require 4 battery cell connection in series
Battery cells connected in parallel.
batteries connected in parallel
A parallel connection of batteries is achieved when the positive terminal of one battery cell is connected to the positive terminal of another battery cell. The same is done to the negative terminals of the battery cells.
In a parallel battery connection, voltage stays constant but current increases.
For example let’s say 2 battery cells are rated 1.5V and 1A each. If the batteries are connected in parallel then their combined ratings are 1.5V and (1A +1A) = 2A
Application of series and parallel connection of battery cells
A very good knowledge of series and parallel connection of battery cells enables the development of battery packs with with different voltage ratings and capacities.
