Sci Lesson 19/8

For today's lesson, we went through the online worksheet lenses, and the teacher had also clarify with us the important points to take note of when drawing lenses.
First of all, there must be 3 rays present. The 1st ray will be parallel to the principal axis and pass through the focal point on the other side. The second ray will pass through the optical centre and go straight in that direction. Last but not least, the third ray will pass through the focal point and be parallel to the princpal axis on the other side. We had also learnt the different terms that will award us marks when answering questions regarding ray diagram for lenses, for example optical centre, principal axis, focal point, focal length and focal plane.
We had also learnt about the difference between long lenses and short lenses. For example, the image obtained from long lenses is diminished, inverted and real, whereas the image obtained form short lenses is magnified, upright and virtual. Today, I had learnt more on the topic lenses, and also went through some of the lenses questions. Through the questions, I had roughly know what will be the type of questions that will normally come out for lenses. Our teacher had also emphasis on us the importance of the terms when answering and also the drawing of ray diagrams.

Sci Lesson 15/8

Today, we had gone through practical 14, 15, and 16, which mainly covered lenses and lights. Before this lesson, I had actually read up on lenses and lights. However, I was just memorizing the facts and concepts, without really understanding it. After today’s demonstration and experiment by the teacher, I had seen for my own eyes and I had definitely understood more.

I had seen for myself when the lens had converged upon convex lens, and diverged upon concave lens. The teacher had also explained that the more curved the sides are, the shorter the focal length (the length measured from the screen /meeting point of the rays to the lens) will be. We had also done the experiment with prisms and we had made use of the prism to show that reflected rays and emergent rays can only be parallel when the surfaces they enter/leave are parallel too, such as using 2 prisms. Last but not least, we had also learnt about identifying which color of light bend the most/least and whether it travels the fastest/slowest. Apparently, the light ray that reveal the more color bends the most and is the slowest, and vice-versa.

Reflection on Term 3 test

Today we had gone through our science Term 3 test. I had gotten a decent grade and I’m satisfied with it. We had also went through the science test’s answer today and I realised some of the mistakes are mistakes that I should not have made in the test.

After looking at my test paper, I realized that I’m better at theory question, where the question is asking me on my concept and knowledge. I am also quite good in applying these concepts into application questions, such as describing the effects of the food chains etc. However, I am weak at drawing questions, especially when they told us to draw reflected and refracted rays. I find it quite hard to understand exactly what did the question demand for. However, I think the only way to counter this weakness of mine is to practice more. As I practice more, I will get used to the questions and also the type of questions that will normally come out on the test itself. Overall, I am quite satisfied with my results and I hoped to achieve the same result, if not better, for my next test.

Sci Lesson 1/8

Today, our teacher went through the reflection assignment 1 with us and also a quick recap on ecology and nutrient cycle for this Friday test. Though it was just a quick recap, it was really useful. I had been reminded a lot about ecology today, and I’m glad for this recap lesson today.

Some of the things that I had been reminded were to never ever include man in the food chain. The teacher had also remind us that we need not know examples that were out of our syllables, for example plants that we never heard before, as long as we had general knowledge of the different plants in different habitats will be fine. Such examples will be cactus in a dry environment and an orchid in an environment where the temperature is lower. Lastly, our teacher also reminded us the importance of keywords and phrases in our answers, phrases such as “angle of incidence equals to angle of reflection”.

After today’s recap lesson, I am more confident for the test. My questions were raised today too and I believe after this recap lesson, it would definitely assist our class overall results too. I really hope there would be such a similar recap lesson in future tests.

Sci Lesson 29/7

Today, we went through our online worksheets 4 and 5. It is about refraction of light and the application of refraction of light, like periscope etc. Our teacher started on refraction as the test topics were already covered, and thus we proceed on to refraction, before lenses next week.
Today, we basically just recap what we have learnt about refraction last lab lesson. I find this lesson useful, even though we have learnt about refraction last lab lesson. This is because the lab lesson mostly tested our accuracy when doing the experiment. However, today we get to apply what we have learnt into application questions and even drawing the rays. The worksheets have shown us really good examples of how question may ask us about refraction. However, as practice makes perfect, it would definitely be better if we could seek for more questions, and the more we practise, the better we are at application questions. At the end of the class, I'm glad that the teacher gave us 1 more worksheet on reflection so as to prepare us for the test !

Sci Lesson 25/7

Today, we went through the practical that we did last lesson. As I had spent my time last lesson clarifying my doubts, I paid double attention to today's lesson as we go through the practical. However, as I had already done my online lessons worksheets, the practical today was actually just a recap of what I had learnt. Below are a few things that I had learnt and recap today:

When light travels from a less dense medium to a more dense medium, the ray of light is refracted towards the normal. However, when light travels from a denser medium to a less dense medium, the ray of light is refracted away from the normal.

The angles of incidence, refraction are both zero when a light ray enters perpendicularly to a medium with parallel surfaces.

Conditions for incident ray to be parallel to emergent ray:
The surface which the light ray enters is parallel to the surface which the light ray exits and
the light ray enters and exits from the same pair of media.

The critical angle is when the angle of refraction in the optically less dense medium is 90 degrees, and the angle of incidence in the optically denser medium is the critical angle.

Total internal reflection occurs when the angle of incidence is greater that the critical angle and the incident ray is in the optically denser medium.

Today's lesson was more of a recap for me, and I find it efficient too, as I could learnt and remind myself some of the facts. It was truly a lesson in the right time, as the test is just next week, and a lesson for me to recap is very important.

Sci Lesson 22/7

Today, we went to the lab lesson to carry out our experiment on refraction. However, I had decided to use this time to clear my doubts instead, since all the necessary equipment is already present in the lab. Thus, I spent the whole of today's lesson clearing my doubts and it was a really nice feeling when I finally understand some of the concepts.
I had asked the teacher for an example of critical angle, how to realise when is it total internal reflection and not refraction, and also the reflective index. All these doubts were present when I was actually doing the online lesson worksheet, and today I had finally find this suitable time to ask.
My friends also cleared some of their doubt, and I was dumbfounded by the questions they asked too, such as the drawing of light rays if there were two objects together etc. I had also learned from their questions too. I find today's lesson very enriching, in the sense that I had cleared my doubts. Although I did not really do the practical worksheets for this lesson, I'm sure I could finish them at home after I had clarify my doubts.

Sci Lesson 18/7

Today, we went through the online worksheet 3 and abit of Refraction. The science online worksheet 3 is actually a very good paper for us to revise, as it comprises alot of questions that requires drawing, which I am weak in. I am weak particularly in understanding the question, and knowing where to draw the rays. Thus, after going through the worksheets and seeing the diagram, i finally cleared some of my doubts.
Before this lesson, I left most of the drawing questions blank as I have no idea what were the questions asking for. During the lesson, I follow along the teacher and got roughly what the question was asking for. However, today's lesson was not able to clear all my doubts as I am very bad in multi-tasking. Therefore, I suggest the teacher letting us copy the drawings before explaining rather than letting us copy while she explain, which is very confusing and we might missed out some of the important points. Nonetheless, I am glad for today's lesson as I managed to grasp what were expected and a few common mistakes while drawing before we move on. However, there is still some doubt that I had no time to clarify, such as when do we know if we were supposed to draw reflected or incident ray, and probably drawings on convex/concave mirrors instead. That's all for today, I have to go revise now, or if there's time, i would clarify with the teacher tomorrow.