Have you ever wondered what a black hole is? Saoirse has done some research to give you an introduction to these mysterious structures... Well done Saoirse! A black hole is formed when the center of a large star collapses in on itself. This event is called a Supernova. Unlike a Supernova, which is very bright, the resulting black hole cannot be seen as not even light can escape it. So how do we know they even exist? We know they exist because of the way dust, stars and other matter* are affected by it.
When the large stars collapses, their mass is condensed into a very small space. This causes the strength of gravity to increase.
The reason that not even light can escape from a black hole is because anything that enters it is ripped apart by this intense gravitational energy.*
Black holes are generally 10 to 24 times larger than the sun. However there are also ‘supermassive’ black holes which can be up to a million times bigger than the sun! Astronomers believe that ‘supermassive’ black holes can be found at the center of almost all galaxies, including our very own Milky Way.
So where do all the black holes go? In the 1970s, Hawking showed that a black hole will simply evaporate (giving out a final burst of energy) if it is not ‘fed’ more mass*.
*mass=made up of matter, a physical substance.
*gravitational energy=the force/energy caused by gravity.
Emer has spent some time studying the science behind music... Well done Emer!
The Science Behind Music
Music plays a huge role in teenagers lives.
Although we find music as a luxury, it is also a necessity. Research shows that we should listen to more music than we do.
Teresa Nakra, the professor of music at The College of New Jersey says "Music is exercise to the brain". "It engages your brain in different levels of thinking".
When we listen to music the brain dissects the song that we are listening to. The brain is trying to follow the downbeats and upbeats of the drum, while recognizing the different octaves and notes of the horns and the voice.
Research shows that the brain produces brainwaves from music with a strong and defining beat. those brainwaves determines our level of concentration and alertness.
Different types of music has different has different effects on us:
CLASSICAL MUSIC ~ This slows down your heart and breathing rate, this is why you would usually listen to it when you're relaxing.
ROCK MUSIC ~ This clears our minds when in the middle of stressful activities.
POP MUSIC ~ Pop music has the same effect on us as rock music.
BLUES MUSIC ~ Calms down your nerves.
REGGAE MUSIC ~ Calms you down when your angry.
LOVE SONGS ~ Makes you feel better after a breakup.
DANCE MUSIC ~ Makes you feel good.
RAP MUSIC ~ Can alter your mood.
HEAVY METAL ~ Can have a negative effect on your mood.
COUNTRY MUSIC ~ Can lead to depression.
Besides being a background or a mood enhancer, music can also be a person's companion.Robert Young McMahon has said that "music can be or friend, especially in times of loneliness".
When you are faced with a long list of chapters to revise for the summer tests or even the whole book for your state exams in June, it can feel intimidating.
The first thing to remember is that you have already learned this material, so you are not learning it all from scratch. Don't worry if you don't remember everything straight away, when you start to revise, you will recognise a lot more than you expect.
Here is one way of breaking all of that revision into manageable chunks:
Make a list of topics/chapters that you need to revise.
Challenge yourself to get all of the important information in that chapter into one page. You might need to make a rough version first.
Practice answering past exam questions or the questions at the end of the chapter.
Here is an example of the list of topics that my second year science classes need to revise:
My students have done an amazing job of creating a one page summary of topics in physics. Here are a few examples of their work. You can see that even though they are all revising the same topics, each poster is quite different. Using colour and little sketches or pictures helps to make the poster really stand out.
Remember that there are three steps to help you get started:
Welcome back to school everyone! We have only eight weeks to go until the summer tests begin! Second years don't forget to revise your physics calculations and definitions... a lot of them are related to length or distance in some way. I created this chart to show how all of these quantities are connected. Remember, if you have a question, write it down and don't forget to ask before it's too late!
Eireann has spent some time researching the physics behind roller coasters! Well done Eireann!
At the start
of a roller coaster ride, the cart is pulled to the top of the first hill but
after that, the cart must complete the ride independently. The roller coaster is moved along the track
because the energy converts from potential energy to kinetic energy. The
roller coaster can be wooden or steel, the experience of the ride will change
depending on the material it is constructed with. They can be all shapes or
sizes. It may have a loop or it may not have a loop. Wooden roller coasters sway a lot more
compared to steel roller coasters.
Inertia allows the roller coaster to glide
along the tracks without an engine. Isaac Newton was the scientist who
discovered inertia, it was his first law of motion.
“An object
at rest tends to stay at rest unless acted on by an unbalanced external force.
An object in motion will stay moving in the same speed and same direction
unless acted on by an unbalanced external force.”
Read more about roller coasters at the following websites:
Flotation is the phenomenon related to the relative buoyancy of matter. Understanding flotation is useful, for example when adding material to the hull of a watercraft to keep the hull afloat. Flotation is used in process engineering, as a method for the separation of mixtures e.g de-inking which is a process that takes ink from paper to make it a blank page again.
Density
The density (also known as the volumetric mass density) of a substance is its mass per unit volume. The symbol most often used for density is ρ, although the Latin letter D can also be used.
Density or the volumetric mass of density is calculated by dividing the mass of the object by its volume, e.g:
Mass of object = 5g
Volume = 10cm3 Density = mass/volume = 5g/10cm3 = 0.5g/cm3
How does the human body float in water?
The density of water is 1g/cm3 and the average density of the human body is 1.062g/cm3 so therefore, the human body should not float. But there's an exception to this concept. In the human body, obviously there's extra muscle and fat, in ordinary water, fat will float because of its density of 0.9094g/cm3 so the more fat you have in your body, the more likely you are to float, but, if you have muscle you will sink because of its density of 1.0599g/cm3.
Paul Buckley is a past pupil of Coláiste Muire. This year, he started his PhD in Atmospheric Chemistry. Paul kindly agreed to answer some questions we had on how he decided on a career in Chemistry and showing us what his job looks like on a normal day. Interview questions by Eireann Griffin and Abby O'Donnell. Well done girls.
What inspired you to pick your career?
The main inspiration for picking my career was the project which I
would be working on. It's a national campaign measuring emissions from domestic
fuel burning. The opportunity to work on a campaign, the results of which will
be debated in the Dáil, have national policy implications and possibly even
shape European policy about air quality really helped me with my decision to
enter research. I also have a strong interest in the health effects of air
quality and this job allows me to continue researching the topic.
How long was your college course? My college course was four years; I did the Chemistry course in UCC.
The PhD in Atmospheric Chemistry will take at least four years to complete.
What is the most challenging part of your job? Like every job there are certain challenging aspects. Conducting a
measurement campaign involves a lot of logistical and practical difficulties
which can be difficult to overcome. It can also involve spending long periods
of time alone. A six week campaign utilizing ten instruments produces a lot of
data which takes a very long time to analyse. There are also some safety
concerns with the job, while I don't work with any hazardous chemicals I do
work with some very high powered lasers which, if handled incorrectly, can
cause serious injury.
Whats the most enjoyable aspect of your job? The most enjoyable aspect of my job is the fact that there are a lot
of opportunities for travel. Once a campaign is finished and the data has been
analysed there are many conferences, both in Ireland and abroad. This year the
group which I am part of will be attending at least two conferences, an Environmental
Science Association of Ireland conference in Limerick and a European Air
Quality conference in France. Also, there are many opportunities to visit other
universities to go on courses or conduct research. For example, I will be
travelling to Japan and the University of Kyoto to study for three weeks.
What is your job title?
I am a Postgraduate Researcher in the Center for Research into
Atmospheric Chemistry (CRAC) in UCC.
What is the key to success in your career?
The key to being a successful researcher is a lot of patience as
things can often not go according to plan and analyzing the data takes a lot of time to complete. Good computer
skills are also essential and an ability to fix any mechanical problems the
instruments may have. Good presentation skills are essential as the results of
the project have to presented at many conferences and meetings, often in front
of large crowds of people.
What did you like the most about Junior Cert Science? In Junior Cert science it was the chemistry section which mainly
caught my attention, in particular the introductions to Atomic Structure and
Bonding. I enjoyed the Light section of the Physics course and in the biology
section I enjoyed learning about the various systems in the body.
Which science subjects did you study in Leaving Cert and what did you enjoy about them? In Leaving Cert science I took Chemistry and Physics. In Chemistry I
again enjoyed the Atomic Structure and Molecular Structure sections, I also
enjoyed the Atmospheric Chemistry section and the Environmental Chemistry
section on water. In Physics I enjoyed learning about Light, its various
properties and how to manipulate it, I also enjoyed the section on Modern
Physics learning about the electron, nucleus and nuclear energy. I found the
Particle Physics section to be the most interesting part of the Physics course.
What other subjects did you enjoy in secondary school?
I obviously enjoyed Chemistry in secondary school but I also really enjoyed Physics. Outside of science, I really enjoyed History and French.
Thank you Paul for taking the time to answer all our questions!
This amazing article was researched and written by Saoirse Flanagan.
On the night of September 27th a Total Lunar* Eclipse of a Super Full Moon was visible in North America, South America, West Africa and here in Europe. So what is a total lunar eclipse? It is when the moon appears darkened as it passes into the earth shadow that is cast from the sun behind the earth; the Sun, Earth and Moon to form a straight line.
The eclipse in September was especially rare because it was an eclipse of a Supermoon. This meant that the moon was at its closest point to the earth, therefore looking larger and brighter to us on earth. No special equipment was needed to view this eclipse and protective eye wear also wasn’t necessary.
A Total Lunar Eclipse can also be called a Blood Moon because the earth’s atmosphere refracts* sunlight and lights up the moon surface. Only the longer wavelengths of the light spectrum reach the surface and therefore giving it its red colour.* A Blood Moon is also commonly used to describe a tetrad. What is a tetrad you ask, it is four successive total lunar eclipses, with no partial lunar eclipses in between, each of which is separated from the other by six full moons.
*Refraction-The bending of light when it goes from one medium to another.
*Lunar-Something relating to the moon.
*Light Spectrum and wavelengths-To read more click here.
Thank you Saoirse for this fantastic article!
Submissions are welcome from all students in Coláiste Muire. Call into the computer room at Tuesday lunchtime to meet the blog team and get started.
Sound is produced when particles vibrate.
A loudspeaker creates sound because is causes the air around it to vibrate in a pattern of waves that reaches your ear... see the animated version here.
The sound of your voice is produced when your vocal chords vibrate as air is passed over them.
Hearing
The ear is a sense organ which detects sound vibrations. Exposure to very loud sounds can cause damage to your hearing.
The outer ear collects the sound and channels it along the ear canal.
The middle ear (ear drum and tiny bones called hammer, anvil and stirrup) conducts the sound into the inner ear.
The inner ear converts the sound energy (vibrations) into an electrical signal which can be sent to the brain.
The auditory nerve is a sensory nerve which sends electrical signal to the brain.
This animation shows the structures in the ear very clearly.
Sound needs a medium to travel through
Because sound is transmitted through the vibration of particles, sound needs a medium to travel through, such as air or water.
A vacuum is a space that is completely empty of matter. There are no particles in a vacuum. Sound cannot travel through a vacuum.
This animation shows a bell inside a jar. When all the air is drawn out of the jar, and a vacuum is created, you can no longer hear the sound of the bell.
Because sound cannot travel through a vacuum, this means that sound cannot travel in outer space.
This article talks about sound at high frequencies... and how students can hear sounds that teachers probably cannot hear!
Speed of sound
Sound travels more quickly through materials that are more dense.
Check it out: tap your finger lightly on the desk. You probably hear a quiet sound. Now lay your ear on the desk and tap again. Can you hear a difference?
Sound can travel through the solid material of your desk more quickly than through the air.
Sound travels faster through liquids than it does through gases, such as air. So the speed of sound in water is 1500 metres per second, while the speed of sound in air is only 340 metres per second.
Thunder and lightning
Thunder and lightning originate at the same moment. However you can often see the lightning before you hear the thunder. This is because light travels faster than sound. Learn how to calculate how far away you are from the storm here.
Echoes
Echoes are reflected sound.
Ships use echolocation to measure the depth of the sea below them.
Fishing boats can also use echolocation to detect shoals of fish swimming beneath the boat.
Remember that sound is a form of energy, caused by vibrations. Here is a video of an Irish physics teacher demonstrating that sound is a form of energy. Energy is the ability to do work or to move something. The sound energy from the speaker causes the flame of the candle to move.
Knowledge check:
OP40 Show that sound is a form of energy, and explain
that sound is produced by vibrations
OP41 Show that sound transmission requires a medium
and that echoes are reflected sound
OP42 Appreciate that the ear
detects sound vibrations and that exposure to very loud sounds can cause damage
to hearing
OP43 Recall that the speed of sound is less than the
speed of light
OP44 Explain the time lag between seeing and
hearing the same event
Post compiled by Ms McCarthy. The website thephysicsteacher.ie contains many helpful links which I have used in this blogpost.
