Archive for March 2008

Testing Times (part 2)

March 10, 2008

examstressStress can be a good thing. A little stress helps you focus and direct your efforts to the maximum output. Everybody knows this is true – have you ever tried to study while sitting outside on a nice, sunny, warm day, with a pleasant breeze? Did you find yourself relaxing, feeling a bit sleepy? Contrast this to the night before an important test – did you find that you were able to stay up late, studying later? Both of these are natural physiological and psychological reactions to stress (or the absence of stress).

But what about when the stress gets to be too much? Too much stress doesn’t give you an advantage or direct your energy effectively. It can cause you to panic, and even have anxiety attacks. How do you best control your stress to a helpful level? Well, it’s all about preparation and organisation. Stress develops when you lose control, and you feel that work is getting away from you. So the first and most important strategy is planning – you need to know what you have to do, and when you have to have each task done by. This means using your diary – and using it well. There will be another post later about how to use your diary/ planner, but for now, the important thing is to write every task into your diary immediately on receiving the information, and onto the year planner as well. You need to write a list for each assessment task telling you what must be done, and then schedule time for each task during your study time.

Lack of preparation can mean an exam crack up:


Diffraction Dilemmas!

March 9, 2008

Ocean Wave Diffraction Diffraction is a strange phenomenon that occurs any time light interacts with a opaque boundary. In the picture to the left, ocean waves that encounter the gap between the peninsula and the islet are diffracted into the bay. You can see the straight waves approaching from the bottom of the picture and the waves becoming curved after they pass through the gap. This behaviour is easy to see when the wavelength of the wave are so large as to be visible, but what about when they are so small that you cannot see the individual waves, like in light?


Lights, Camera, REFRACTION!

March 8, 2008

water drop refraction Look at this drop of water, perched on a grass stalk (click to see a larger image). Within the water, a distorted image is present. This is caused by refraction of light coming from distant sources, being brought into focus by a lensing effect from the water drop. Refraction is present all the time, but just like reflection, our minds don’t process it well. When we look at something, there is the implicit expectation that the light that reaches our eyes travels in straight lines. The fact that it hasn’t in some cases, due to refraction, causes the optical illusions you see in the picture above and the movie below: