Physics Tricks | Cloud In A Bottle

Now-you-see-it, now-you-don't! This is a good trick for people to try themselves, watching a cloud appear and disappear before their own eyes.

• plastic bottle with cap (fairly flexible e.g. from most soft drinks)
• water
• match

1. Place a splash (~1 teaspoon) of water into the plastic bottle.

2. Light the match and make sure it is burning well, then drop it into the bottle
3. Quickly screw the cap on, and squeeze the bottle with your hand five or six times (for larger bottles you may have to do it slightly more). You should see a cloud form in the bottle, then magically disappear when you squeeze it.

4. Pass the bottle around the audience to give everyone a chance to
experience it for themselves.

How does it work?
Clouds are formed when water droplets in the air cool and then collect on dust particles. In this demonstration, the dust particles were provided by the smoke from the match. The air inside the bottle was cooled by releasing the pressure after the bottle was squeezed. The temperature is changed by squeezing the bottle: the amount of air within the bottle is constant, but squeezing the plastic bottle changes the volume of the gas. Expanding the bottle causes a lowering of the air temperature – in this case, enough to cause the water gas to form a liquid – the cloud.

Tips for Success
Try adding a small amount of food colouring to the water – it can help to increase the visibility of the effect.

Serving Suggestions
This works well for small groups of people of all ages. It is particularly applicable in outside environments where you can actually see clouds and potentially discuss the science behind them.

Did You Know?

This demonstration involves building a small cloud chamber exactly like those used to first record the tracks of subatomic particles (alpha and beta radiation) by Charles Wilson in 1911. Wilson (who was born on St Valentine’s Day) was awarded the Nobel Prize in 1927 for this discovery.

Microsoft in Hindi

Microsoft has announced the availability of Operating System in Hindi. Pls see some of the phrases you will be using tomorrow.

Bill Gates had announced that Microsoft plans to release a windows version in Hindi. Here are some Windows related terms that are to be used in the Hindi version of ...........

Khidkiyan'DoHazar ( Windows 2000 ):

1.Phaail = File
2.Bachao = Save
3.Aise Bachao = Save as
4.Subko Bachao = Save All
5.Mujhe Bachao = Help
6.Dhoondo = Find
7.Firse Dhoondo = Find Again
8.Hilao = Move
9.Dak = Mail
10.Dakiya = Mailer
11.Paas se dhekho = Zoom
12.Door se dhekho = Zoom Out
13.Kholo = Open
14.Bandh Karo = Close
15.Naya = New
16.Purana/Khataara = Old
17.Badli Karo = Replace
18.Bhaago = Run
19.Chhaapo = Print
20.Dekh Ke Chaapo = Print Preview
21.Nakal Utaaro/Kaapi =Copy
22.Kaato = Cut
23.Chipkao = Paste
24.Payshal Chipkao = Paste Special
25.Goli Maaro = Delete
26.Nazaara = View
27.Hatyaar = Tools
28.Hatyaar Khamba = Toolbar
29.Khuli Chaadar =Spreadsheet
30.Kalti Maaro = Exit
31.Ped = Tree
32.Thooso = Compress
33.Chooha = mouse
34.Tik Karo = Click
35.Tik-Tik Karo = Double Click
36.Idhar-se-Udhar – Forward
37.khamba= Scrollbar

Additional Softwares


2. Double Click with the left mouse button-Chuhe ke baye kaan ko zatpat do baar marodkar 'tadak-tadak'=(clik-click)kariye

FAULT) - Sarvasaadharan Suraksha Mein Gadbad

4. 'This program has
performed an illegal operation - "Abort,Retry or Ignore" ?
"Is karyakram ne gairkanooni kaam kiya hai -zatak se bandkaro (abort),Koshish karte raho/Hum honge Kamyaab retry), Goli Maro (Ignore)"

5. MICROSOFT POWERPOINT – "AtiSukshma Mulayam ShaktiBindu"

6. MICROSOFT WORD 6 – "AtiSukshma Mulayam Shabda Cheh"


8. FOXPRO – "Lombdigiri (Lomiree) mein Maahir"

9. MICROSOFT VISUAL C++ - "AtiSukshma Mulayam Nazaaraa C adhik hi adhik"

10. OFFICE 2000 –"Karyalaya 2000 mein"

11. Internet Explorer –"Taaron ke Jaal ka Sanshodhak"

12. Lotus Notes - Kamal ke Ruppeye"

13. ACCESS DENIED - " Ghusne ki Agya nahi "

Straw Oboes | Physics Tricks

A noisy, amusing demonstration of the physics of music. It can take a bit of practice to get exactly right, but it's well worth the effort.


• straws (need to be straight – cut off the bendy bits if there are any)
• scissors


1. Flatten one end of the straw ~2cm from the end to the tip.

2. Make two cuts in the now flattened end of the straw, to form a triangular tip.

3. Insert the triangular tip of the straw into your mouth and blow hard. You should hear a loud 'buzzing' sound.

4. While blowing on the straw oboe, get a volunteer to cut the straw shorter, ~1cm at a time. With each cut you will hear the pitch of the oboe sound go up.

How does it work?

The flattened triangular tip acts like the reed found in most wind instruments. Blowing on the reed causes the straw to vibrate. A standing wave pattern is created along the length of the straw, which we hear as sound. As you shorten the straw you shorten the wavelength of the standing wave pattern and therefore increase the pitch of the note.

Tips for Success

It can take some practice to get the right sound – if it doesn't work straight away then slowly move the straw in and out of your mouth whilst still blowing until you hear the sound. Definitely a good demonstration to practice before performing it in front of an audience!

Serving Suggestions

This is a good demonstration to attract a crowd due to the amount of noise involved. Younger kids in particular will love hearing the effect of the pitch going up as the straw is cut shorter and shorter. They will also enjoy making their own straw oboe as part of the demonstration, which they can keep afterwards.

Did You Know?

As long ago as the fifth century BC Pythagoras and his followers were experimenting with standing waves and calculating the values of their harmonics. Another way to set up a standing wave is to blow across the top of a beer bottle. In this case the note gets deeper as you drink the beer (sorry, tune the instrument). Pythagoras refused to let his followers eat beans for fear of flatulence; fortunately, no such effects are associated with beer drinking.

Exiting Windows the Cool and Quick Way

Normally it takes a hell lot of time just Shutting down Windows, you have to move your mouse to the Start Button, click on it, move it again over Shut Down, click, then move it over the necessary option and click, then move the cursor over the OK button and once again (you guessed it) click.This whole process can be shortened by creating shortcuts on the Desktop which will shut down Windows at the click of a button.

Start by creating a new shortcut( right click and select New> Shortcut)
Then in the command line box, type (without the quotes.)

'C:\windows\rundll.exe user.exe,exitwindowsexec'

This Shortcut on clicking will restart Windows immediately without any Warning. To create a Shortcut to Restarting Windows, type the following in the Command Line box:

'c:\windows\rundll.exe user.exe,exitwindows'

This Shortcut on clicking will shut down Windows immediately without any Warning.

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