Thursday, 25 December 2014

These Eggs Can Breakdance!

What do you need?
You will need a hard-boiled egg or you may try this with a special type of spinning top (as shown in the picture below).

What to do?
First, get a hard-boiled egg. Lay the hard-boiled egg on its side on a table or a smooth, flat surface. Spin the egg as fast as you can.  Observe what happens. Try again and repeat with the special spinning top, if you have one. 

What happens?
Can you believe it? It inverts itself halfway & spins upside down! 
This is because of the friction between the eggshell and the tabletop which pushes the spinning egg up. But this only happens if you spin the egg fast enough!

While it spins, the egg appears to defy gravity.

Watch this video!

Friction destabilizes the egg’s spin and causes it to shift position. Some of the kinetic energy (KE) of the egg’s spin is converted to potential energy (PE).  When standing on end, the egg has more potential energy and less kinetic energy (for a few seconds).

Shared by Azni
Learning Specialist, Petrosains

Thursday, 18 December 2014

Yang Mana Satu Cacing Jantan, Yang Mana Satu Cacing Betina?

Yang mana satu cacing jantan dan yang mana satu cacing betina? Bagaimana untuk membezakan jantina mereka? Cuba perhatikan pada keadaan fizikal cacing tanah seperti dalam dibawah. Bolehkah kita mengetahui yang mana satu memiliki organ pembiakan jantan dan yang mana satu memiliki organ pembiakan betina?

Sebenarnya, memang tiada perbezaan daripada segi fizikal pada cacing tanah yang boleh membezakan jantinanya. 

Cacing tanah adalah 'hermafrodit' iaitu memiliki kedua-dua organ pembiakan seks jantan dan betina pada setiap seekor cacing tanah. Walaubagaimanapun, seekor cacing tanah perlu mengawan dengan cacing tanah yang lain bagi menghasilkan telur supaya spesies ini akan terus membiak. 
Kokon cacing tanah yang seakan-akan menyerupai bentuk buah lemon
Imej kredit: U.S. Department of Agriculture
Gambar diatas adalah kokon cacing tanah. Telur-telur yang terhasil daripada  proses pembiakan akan berada di dalam kokon sebelum ia matang untuk menetas keluar. Pada kebiassannya, terdapat satu telur atau lebih dari satu telur dalam setiap kokon.

Cacing tanah mungkin menggelikan tetapi spesies ini memiliki banyak keunikkan semulajadinya yang tersendiri. Berikut adalah di antara pautan yang dicadangkan bacaan selanjutnya:

Pelajari dengan lebih mendalam tentang cacing tanah dan mencuba untuk menyentuhnya di Petrosains bersempena Face Your Fears! sehingga 4 Januari 2015 ini

Friday, 12 December 2014

Incredible Toothpicks!

What do you need?
All you need are 5 toothpicks, a syringe and water.

What to do?
Take 5 thin toothpicks and carefully snap them in half.  Ensure both halves are still attached. Then arrange the toothpicks in a circle with the bends touching each other. Drop a very small drop of water to the centre of the circle. Observe what happens.

Watch this video to see what happens!

What's going on?
The wooden toothpicks are made up of dry porous fibers. When water is dropped onto the snapped toothpicks, it moves inside from the  broken part and continues along the length to the pointed tips. The capillary action or water traveling inside the toothpick causes the toothpicks to glide as they straighten. 

Shared by Azni
Learning Specialist, Petrosains

Tuesday, 2 December 2014

Susun Baju Pun Ada Sains?

Ruang manakah yang hendak dipenuhkan terlebih dahulu apabila kita hendak menyimpan pakaian pada rak baju? Sekiranya rak baju tersebut mempunyai tiga lapisan para, di manakah seharusnya kita menempatkan pakaian-pakaian  yang tebal dan berat? Apakah kesan yang akan berlaku pada rak baju sekiranya muatan pakaian atau apa sahaja benda yang diletakkan di atasnya diletakkan begitu sahaja tanpa meneliti konsep sains di sebaliknya?

Jom lihat video di bawah untuk beberapa contoh aplikasi konsep kestabilan dalam kehidupan seharian seperti bagaimana untuk untuk menyusun baju agar rak baju sentiasa berada dalam keadaan yang stabil.  

Apa yang berlaku?
Pakaian yang tebal dan berat sepatutnya diletakkan pada bahagian bawah sekali pada rak baju manakala yang lebih ringan diletakkan pada bahagian atas bagi memastikan kestabilan rak baju.

Kestabilan sesuatu objek dipengaruhi oleh ketinggian dan keluasan tapak sesuatu objek. Semakin besar keluasan tapak objek, semakin stabil objek itu. Objek yang rendah adalah lebih stabil berbanding objek yang tinggi walaupun objek tersebut mempunyai keluasan tapak yang sama.

Walaubagaimanapun, memang ada banyak perkara yang kita lakukan seharian yang mengaplikasikan konsep kestabilan dan ini hanyalah salah satu contoh sahaja . Jadi, pastikan kita sentiasa meneliti faktor-faktor yang mempengaruhi kestabilan supaya kita dan segala peralatan rumah sentiasa berada dalam keadaan stabil dan selamat!

Posted by Ayu
Learning Specialist, Petrosains

Friday, 28 November 2014

PETRONAS Streetsmart Road Safety Exhibition is Back in Petrosains, KLCC!

The PETRONAS StreetSmart road safety exhibition is now at Petrosains, The Discovery Centre, Level 4, Suria KLCC, PETRONAS Twin Towers, 50088 Kuala Lumpur, from 22 November 2014 to 31 May 2015. 

There are lot's of activities on offer!
  • Road safety science shows
  • Quizzes on road safety and a variety of games
  • Workshops on road safety
  • Interactive activities for the whole family
and also, a special appearance by the PETRONAS StreetSmart Mascots!

Here are some photos of the exhibition!

So don't wait because admission is FREE!
Come visit PETRONAS StreetSmart, learn something about road safety and celebrate the wonders of science in a hands-on, and interactive way that's fun for the whole family!

Operations hours:
Tuesday - Friday = 9.30am until 5.30pm
Saturday, Sunday & Public Holiday = 9.30am until 6.30pm

Closed on Mondays except during School Holidays & Public Holidays

Find out more at 



Monday, 24 November 2014

Bernoulli's Dancing Skirt!

Let's watch this video!

The skirt rises as the girl in the video spins. This happens because when the girl dances & spins with high velocity, the speed of the moving air on top of the skirt increases which will create a low pressure area and the speed of moving air below the skirt decreases which creates a high pressure area. Thus, according to Bernoulli's Principle, the difference in pressure makes the skirt rise up.

That is why it is called 'Bernoulli's Dancing Skirt'!

Posted by Ayu

Tuesday, 18 November 2014

Super-duper Computers!

Supercomputers!  We know it’s a combination of super + computer.  You get it, but what is it?  What does it do?  What’s so super about it?  Can it perform fantastic stuff just like Superman but of course not in the same vein? 

According to the 43rd edition (June 2014) of the twice-yearly TOP 500 list of the world’s most powerful supercomputers, the Tianhe-2 is the world's most powerful supercomputer - third time in a row!  Developed by China’s National University of Defense Technology, it has a performance of 33.86 petaflop/s and is used as a "research and educational" tool.

Image credit: Wikimedia Commons

But hey, what’s a petaflop?  It’s a measure of a computer's processing speed and is expressed as a thousand trillion operations per second. 
[Check out:].

How fast is fast? Supercomputers have the ability to process massive and complex data, so it needs to be extremely fast.  Imagine a supercomputer with a top speed of 27 petaflops or 27,000 trillion calculations per second, this means it is hundreds of thousands times faster than our top-of-the-line PC.  It won't fit on a desktop as it occupies a space the size of a basketball court [Source: How Stuff Works]!

IBM Blue Gene P Supercomputer
Image credit: Argonne National Laboratory

So, what does it do?  

Predict the weather. 

Research on the climate and global warming. 
Molecular modeling - to compute the structures and properties of biological compounds. 
Simulations – e.g. the effect of wind and turbulence on an airplane; and the simulation of the effect of a nuclear weapon if it were to be detonated. 
In the US, the military uses supercomputers for: 
         - Testing new vehicles being engineered & to see how they will function in combat. 
       - To give soldiers a simulation of how it will be in the new vehicle & how they need to react in certain situations.
      - Used for military pilots who go into a simulator to see how to react during combat situation

There’s much more stuff it could do and they are used by different people for a variety of reasons. How much does one cost?  It may cost between USD100 million - USD250 million for design and assembly.  This does not include maintenance costs.  Electricity bills to run it may cost about USD9 million a year!  Functional-wise it lasts for about 2-3 years. Yes, not cost effective but the reason it is built is altruistic - to save the world!

Shared by Azni
Learning Specialist, Petrosains

Saturday, 15 November 2014

Celup Tangan Dalam Minyak Panas Tapi Tidak Melecur!

Betulkah? Apa kata 'sains' mengenainya

Demonstrasi sains ini seolah-olah seperti 'silap mata' tetapi sebenarnya tidak!
Jom lihat video ini

Apa yang diperlukan?
Kita perlukan sebuah bekas kaca yang tahan panas (seperti bikar), sumber api, minyak masak, dietil eter dan cermin mata keselamatan. Sebagai langkah berjaga-jaga, pastikan aktiviti ini dilakukan di tempat yang berdekatan dengan sinki ataupun sediakan sebaldi air di sebelah anda.  

Bagaimana cara melakukannya?
Masukkan secawan minyak masak ke dalam bekas kaca. Kemudian masukkan 3 sudu cecair dietil eter ke dalam bekas yang sama. Panaskan di bawah nyalaan api. Perhatikan bekas kaca. Apabila buih-buih udara kelihatan, ini bermaksud ia sudah mendidih. Alihkan sumber nyalaan api. Celupkan tangan ke dalam bekas sehingga paras minyak sahaja. Elakkan dari mencelup tangan hingga ke dasar bekas kaca!

Apa yang berlaku?
Tangan tidak melecur! Ini adalah kerana yang dilihat 'mendidih' itu sebenarnya ialah cecair dietil eter yang berada di bahagian dasar bekas kaca kerana takat didihnya rendah iaitu 24.6 darjah Celcius (maksudnya baru sahaja dipanaskan, ia terus mendidih). Manakala takat didih minyak masak adalah 350 darjah Celcius. 

Pada ketika cecair dietil eter sudah mendidih, minyak masak belum lagi mencapai takat didihnya. Jadi kerana itu apabila kita celupkan tangan, ia tidak melecur! Minyak masak berada di atas bekas kaca kerana ia adalah kurang tumpat berbanding cecair dietil eter. Cecair dietil eter pula adalah lebih tumpat berbanding minyak masak dan kerana itulah ia berada pada bahagian bawah bekas kaca!

Posted by Ayu