iExel Blog

Have you ever experienced a ride on a Tower of Terror II roller coasters located in Queensland, Australia and if so why do people get so exited about that? What is so fascinating about getting in and riding in a roller coaster? If you are a student who learn physics or who is interested on physics you may have heard the physics behind it from your teacher in school or your private tutor in Australia.

The excitement of a roller-coaster is also due to the unusual accelerations experienced during the ride, the amount of the centripetal acceleration acting on the rider is amazing, it produces apparent forces from weightlessness to increased weight and being thrown sideways. These accelerations have effects on the human body, depending on the direction in which they act. Mostly the value of acceleration changes in between 2g to 5g and it varies from one place to another. So what do we mean by the term ‘acceleration’?

In physics, acceleration is the rate of change of velocity over time. Normally the acceleration is the rate at which an object speeds up or slows down. However acceleration describes the rate of change of both the magnitude and the direction of velocity. It is measured in meters per second squared in SI units (m/s²).

Instead of the acceleration, which is the rate of increase of the velocity the rate of decrease of the velocity is called the deceleration as well as retardation. Other than these in Physics we talk about other type of acceleration which is called the centripetal acceleration which is caused by the change of the direction of the velocity through out a rotational motion and this is the acceleration we feel when we ride in a roller coaster. What is more important about centripetal acceleration is that it is always acting towards the centre of the circle which the body travels.

In basic physics, when a body of mass ‘m’ travels with an acceleration of ‘a’ it says that the net force acting on the body can be found by multiplying the mass of the body by its acceleration and it is one of the famous Newton’s law of the motion. Everybody knows that it is the most important equation where acceleration involves with.

So what is so fascinating about the acceleration? In our day to day life we always deal with acceleration. If you’re in a car, the velocity is the speed at which you’re going in a certain direction. As you accelerate you get pushed back into your seat. As you decelerate by breaking you get pulled forward.  Another example people often discuss is the swing of a certain object, where the acceleration and deceleration are constantly changing like in a simple pendulum.  Another example is a baseball thrown outwards, or a bullet fired. Neglecting the air resistance, they have a constant velocity forward and acceleration downward due to gravity. This is called the acceleration due to gravity as well.

It is not wrong if we say, carbon is the most important and widely used element of the periodic table. Carbon compounds, specifically covalent network compounds are used significantly in many areas of Science.

We know that some of the many forms or allotropes of carbon include Diamond, Graphite, Amorphous carbon, Carbon fibres and last but not the least the new avatar is the carbon nanotube.

Carbon nanotubes or CNTs are allotropes of carbon with a cylindrical nanostructure and belong to the fullerene structural family. These carbon macromolecules possess the innovative properties which widen their use in areas such as nanotechnology, electronics, optics and other fields of material and architectural fields. They get their name from their size, since the diameter of a nanotube is on the order of a few nanometers, which is around 1/50,000^th the width of a human hair.

Nanotubes can be classified in to two types; they are single walled nanotubes, SWNTs and multi-walled nanotubes, MWNTs.  SWNTs have a diameter close to 1 nm (nanometer) and the length being many million times longer. Their structure can be thought of as a single layer of atoms (carbon) wrapped around a cylinder. In case of MWNTs, there are multiple rolled layers of graphite.

Despite having a very useful and significant structure, nanotubes also have remarkable physical properties. Carbon nanotubes are the strongest and stiffest material till date. It has very high tensile strength and hardness. They can withstand a pressure of about 24GPa without deformation. They are also very good thermal conductors and in terms of electrical conductivity they are semi conductors. All these properties put together make them perfectly suitable for an elevator cable. An elevator to the SPACE.

A space elevator is a long cable extending from our planet’s surface into space with its center of mass at geostationary Earth orbit (GEO). Electromagnetic vehicles would travel along the cable and serve as a mass transportation system for moving people, payloads, and power between Earth and space. The cable for this project has to have many significant properties. It should not get distorted or damaged due to the external space environment, it should be able to withstand the load being moved across (people, payloads), and it should have a long wear and tear time. All of these properties are met by carbon nanotubes. Therefore, scientists are looking forward to use carbon nanotubes to achieve this project.

All these are some of the applications of the carbon nanotubes. It is important to share such interesting and important information with the new generation students of year 11s and 12s as it would greatly increase their ability to better understand the impact and significance of the topic- covalent network compounds. Teaching in Australia should be credited for their more practical curriculum. There are many professional online tutors in Australia who makes their classes very interesting and attentive by using such real examples for their explanation. One such organization which provides professional online tutors in Australia is www.iexel.com.au .

Chemical Hazards in a laboratory

Good laboratory practice is essential if laboratories are to be safe places to work. When working in the laboratory you should always remember to wear safety glasses & you should try to minimize contact of chemicals with your skin by wearing rubber gloves.

Disposal of chemicals is another thing which you need to think about. You should never throw organic solvents into the sink.

Chemical Hazards in a laboratory are of four types.

§  Flammable Hazards

§  Reactive Hazards

§  Corrosive Hazards

§  Toxic & carcinogenic material

Flammable Hazards

Flammable Hazards are due to flammable liquids or the vapor produced from such a liquid. For an example liquid bromine causes deep & painful wounds when it is spilled on the skin.

Reactive Hazards

Reactive Hazards are due to oxidizing agents & explosives. Chlorine dioxide is a strong oxidizing agent which is used as bleach in water purification. It can act as a severe respiratory irritant & exposure to concentrations of up to 1ppm has been fatal.

Corrosive Hazards

Corrosive Hazards are due to chemicals that cause visible destruction. Corrosive substances cause destruction of living tissue by chemical action at the site of contact.

Hydrofluoric acid (HF) is highly corrosive to body tissue, even in dilute solutions

Toxic and carcinogenic material

Heavy metals, alkylating agents such as methyl iodide can act as toxic materials which causes cancer in humans.

The precautions which we can take to avoid chemical hazards can be summarized as,

§  Reading the chemical safety information

§  Dress appropriately

§  Assessment of possible hazards before carrying out a laboratory experiment.

§  Avoid tasting or sniffing chemicals.

§  Avoid casually disposing of chemicals down the drain.

Many organizations are working on improving good laboratory practices to avoid possible accidents that can occur due to Chemical Hazards.

One such organization is Chemical & laboratory safety institute of Australia which provides guidelines and laboratory safety manuals for science educators who are teaching in Australia.

Material Safety Data Sheet, which is also known as MSDS are freely available online for each an every chemical and MSDS are widely used by professional online tutors when explaining the properties and safe handling of chemicals.

What is Risk assessment? Before conducting practical work with potential risks a Risk assessment should be done. Assessing risk involves examining the extent of the likelihood of a substance causing harm, in the actual circumstance of the work. That is recognizing the hazards caused by chemicals used and produced, the operations carried out and most importantly the waste management or the safe disposal of the chemicals used and produced.

In order to prevent the accidents which could be fatal at times, always be aware of what is going on around you. If in doubt about any procedure or aspect of safety, please ask a demonstrator or a member of staff.

It maybe clichéd to say but true nevertheless, that we live in an online world. Everything we need is online from shopping to banking, to researching to booking airline tickets and more. Most of our day to day activities are available online, even meeting new friends and chatting with old ones. We don’t need to step out of our homes as the world is at our fingertips.

Life has definitely become faster paced and sometimes it is difficult to keep up. The Internet has reduced travel time and expenses. In the past we may have had to travel long distances to purchase something not freely available close by, now we can simply go to a website, order online and wait for it to be delivered to our doorstep. This has reduced our fuel costs and given us more time to concentrate on the other important things in life. It has all become so relatively easy.

The world of education has also entered this new age. While the Internet may never fully replace the experience of schooling it has become an indispensible aide to us in our academic life. Tuition is part and parcel of schooling at some point all of us need a little extra push to achieve our required goals. Tutors are a standard in our lives, and until recently we needed to either travel to a tutor’s house, a group class, or have a tutor visit us at home.

The Internet has revolutioniszed this. We can now get online tutoring help at home. Australia offers many options in the online tutoring arena making it easy for students to find an option that suits their educational requirements.

It is important for students to compare the rates, the flexibility of the program and know the availability of tutors. Online tuition in Australia is rapidly gaining popularity as it eliminates the need for travel or the expense of having a tutor come to your house. It also allows students to choose a tutoring time convenient to them that fits into their busy life. As the tutoring is conducted online, students can have the benefit of tutors from all over the country and are not limited to those only available close to their homes.

At a time when being ahead of your game is more important than ever, in order to succeed, it is time to give students the heads up with an easy and convenient method of tuition: online tutoring.