Solving Stage 8 Science Progression Test 2025 Paper 1 Walkthrough Part 1

Hello everyone, welcome to solve guide. So we are solving the progression test of the subject science of year 2025. The paper is paper one. the duration for the paper is 45 minutes and the marks allotted the total marks from this paper is 50. And because we'll be solving this in two parts and this is the part one from question 1 to 7 of the total 15 questions. Part two link I'll be uploading in the description. so you can check that out once the video is uploaded. Okay, let's saw the paper. Okay, the first question is look at the diagrams of the joints in the human body. Each joint is circle and draw straight line from each type of joint to match the joint in the human body. Draw only two lines. Okay, so the type of joint and the joint in the human body. you can see the all the different types of joints labeled in this and yeah so you know what I'll be doing is won't discuss the whole all the number all the joints mentioned in this paper what I'll be doing is I'll explain each the name of each joint in the shorts video that you will see I'll upload the same in the link of the same in the description. Right now we'll just mark down the answer and rest if you want to know about all the joints. I'll make quick short video of that and we'll be uploading as shorts. So you can check that out too. Okay. Here ball and socket joint. Ball and socket joint at the hip right there. And the hinge joint near the arm. So that's the hinge joint. Coming down to the sub question subp part Write down the name for the pair of muscles used to move hinge joint. The this one the pair of muscles that are used to move the hinge joint. They are antagonistic. Antagonistic muscles are used to move hinge joint. Okay, let's move on to the next question. Question two is atoms are made of protons, neutrons and electrons. The first one is to write down the charge on proton. Protons are positively charged particles. So the charge on the proton is positive. And then write down the charge on an electron. Electrons are negatively charged particles. So negative. Next is the atoms consist of nucleus surrounded by cloud of electrons. And what hold the particles in an atom together? Now we all know that in an atom center the nucleus is located and then the electrons they move around the nucleus in certain path and here we mentioned that as the cloud of electrons. So what holds the particles and atom together? If you try to recall protons they are present in the nucleus. Protons they are present in the nucleus and they are positively charged and electrons they are moving around the nucleus and they are negatively charged. Now these positively charged protons at the center will you know because they are oppositively charged that definitely creates force of attraction and that's the reason we could say explain what holds the particles in an atom together. So let's write down the answer. Protons are positively charged and electrons are negatively charged. This protons that is the the ones that are present in nucleus and electrons. These protons and electrons attract each other. due to unlike charges. So unlike charges or opposite charges whatever you want you can write. So positively charged protons attract the negatively charged electrons and due to this they keep holding on to each other and thus that's our answer for this question. Let's move to the next part. Okay. Third is Mike is flying in plane from Australia to Canada. The two airports are 15,000 km apart and the flight takes 20 hours. Calculate the average speed of the plane. Include the units for speed in your answer and show you're working. Okay. so here we have 50,000 15,000 kilometers apart. So that's the distance and the flight takes 20 hours the time and we're supposed to find the average speed of the plane. and you're told that include the units for speed in your answer and we have space for it. So we while calculating we'll try to write the units as well altogether and as you're supposed to show the working. So you need to mention the whole thing. I'll be just solving it over here and on the place on the right so that you know what is to be written in this place. So here the we are supposed to calculate the average speed. So average speed is equal to if you remember it's the total distance traveled upon the total time taken to travel this distance. And so the total distance traveled here is 15,000 and the distance is 20 hours. Now as I'm told to include the units for the speed. So why not just start right from here to avoid any confusion. So that's in kilometers and 20 is in hours. Now if further solve this well could because that's paper one and you know there is no restriction for calculators so you could use that or you could just you know this two zeros are and that's 1,500. So * 2 is 1 5 0. So that's 750 kilometers per hour So 750 and the unit is kilome per hour Okay, moving on to the next one. Okay. AIO hammers different nails into blocks of wood. Here we have two blocks, block and block Iiko uses the same hammer, the same force and identical blocks of wood. Explain why she finds it easier to hammer the nail into block instead of block Okay. if you carefully look at the nails he's like hammers she hammers different nails. So let's look at the nails. If you see look at this pointy edge and look this non-pointy one and so and as it says that explain why she finds it easier to hammer the nail into block so this one is easier to get it you know nailed into the block but the one at is difficult or not easier to do. So here if you remember the concept of pressure so pressure is directly proportional to the force and inversely proportional to the area of the application. So here lesser the area more is the pressure. So as the nail is hammered into block has smaller area. So as the this sharp edge it has the smaller area. So when it is hammered the pressure is applied more over the block by the nail and so it easily gets into the block. if you look at the nail if you look at the surface over here so the pressure gets divided and so it's not easier to you know just let the nail mean the part block be nailed over this so let's start explaining this thing based on the concept of pressure is equal to force upon area So we'll just include this area and the pressure relation and explain it. So what I'm going to write over here I'll just write here. So less the area as it's inversely proportional. So lesser the area is the pressure. Here the nail hammered into Block has smaller area. So pressure is more Now pressure is more compared to block mean the nail which has been you know hammered into the block compared to that here the block the nail that is going to hammered has will apply more pressure and so it easily gets into the block compared to block Okay, let's move to the next one. The fifth question. There are millions of asteroids in the solar system. Okay, so the table shows the information about four objects in space here. Object and We are given the information that how far it is from the sun. The distance from the sun it's guess it's in increasing order. Yes. distance in kilometers. so distance from the sun in kilometers. And okay, not distance, that's diameter in kilometers. So this one is the largest. Okay. And year of discovery. Okay. That's 1631, 1807, 1801, 1846. Now, two of the objects are planets and two of the objects are asteroids. Which two objects are asteroids? Okay. The characteristics of planets and asteroids. I'll be using that as reference to imagine what could what might be the asteroids. just let's let's look at the comparison of their distance from the sun and the diameter. So here if look at them this is 353 triple 0 and the diameter in kilometers is so less. Again this is the distance from the sun is pretty much far but the diameter is so less and hence if you look at these both because they are planets they are huge. Yes. So diameter should diameter will be more. So they are planets and definitely so here asteroids which are very smaller in size compared to the planets and that's the characteristics that we use as the reference and so the two objects which are asteroids are the ones which have less diameter. Okay. So here they are and and because here we are sold explain your answer. So as we know they are smaller than the planets right so their diameters is less. So asteroids are smaller than any planet. So the ones with less diameter are asteroids. Okay. So now the bless looks at the description of some objects in the solar system. Here the object Beno collection of stones collected by connected by gravity series three quarters rock one quarter water hailbop ice dust and gasa silica rock cleopetra nickel and iron center surrounded by rock okay okay objects in the solar system that's what we have so blessie knows that four of the objects are asteroids because of their description and which object is not an asteroid. Here again we'll look at the part of the the characteristics as we all know that all the asteroids they're made from rocks. So if you look at all of them here there is if you look at the words in the description stones rock ice dust gas no rock over here silica rock and clearra surrounded by rock. So yes we have the answer is the object that is not an asteroid because it is not made from rock. So, hail rock and so we explain the answer using the same description. Asteroids are made rocks while Hail Bob is made up of as you know ice, dust and gas. Okay, let's move to the next one. Vesta is one of the largest asteroids in the solar system. Okay. And Vesta orbits around the sun between the orbits of Mars and Jupiter. Now describe how Vesta was formed. Now again as we know it's formed all the asteroids they are formed from the rocks and here it's not just Vesta. If you are asked the same thing about any asteroid how it was formed. So we all know that when solar system was being formed and you know billions of years ago it is formed from the rocks that are left over from the formation of the planets. So during the formation of planets whatever the leftover rocks are present these asteroids are those and so how was formed? So not only for any asteroid you would use the same answer. let's write down was formed billions of years ago. During the formation of solar system. And so and it was formed of as we know it was formed from the rocks left over. from the formation of planets. Okay. So, Vesta was formed billions of years ago and use two statements as see the marks allotted to this is two. So, would use that as reference in this case. Okay. let's move on to the next question. So this question is about pollution in ecosystems. The diagram shows the impact of releasing chemical waste into the sea. You see this chemical waste that enters the sea. Now contains 2 ppb of mercury. Now plankton takes in this mercury compounds but cannot excrete them. The small fish that feeds on the plankton. Now large fish feeds on the small fish. Then fishermen they catch or eat the larger fish already. So the seawater normally contains 0.1 ppb of mercury and the chemical waste also sense 2 ppb of mercury. So the concentration of mercury has increased lot. Yeah. So minimata disease affects the nervous system and this disease is caused by the levels about 20,000 about 20,000 ppbs per billion of the mercury in the body. Explain why the fishermen develop minimamata disease. Of course it's the consumption and excretion. So ideally if you look at it you know mercury is poisonous for humans and as we see it is found at lower levels you know you know any food chain that we look at but as it moves above the food chain or the top of the food chain its concentration increases because from every source the mercury keeps on adding and so you know the increase takes place and this is called Bio accumulation. If you have studied in your syllabus that you know it keeps on accumulating and mercury cannot be excreted you know so the accumulation takes place and ultimately this accumulation cause serious nervous system effects. at lower stages it is not visible but when the accumulation keeps on continuously like here if we talk about the fishermen they consume this fish and over time the bio acccumulation leads to excess of mercury in the body and ultimately it causes the disease minimatter that affects the nervous system. So here the question is for three marks. So let's write that down accordingly. First that about mercury. Mercury is poisonous. It is found at low levels at the bottom of wood chains. And much higher in concentration towards towards top of food chain. Now that was general information where we say where it's found and this leads to bio acccumulation. Now bio accumulation occurs. When mercury cannot be excreted, excuse me, in individuals. So this accumulation then further leads to the disorder. So this build up causes serious nervous system effects. not visible at lower stages. And so fishermen develop men coming from their food. Now as said it is not initially visible to them you know the effects and everything but slowly slowly as the mercury is you know it doesn't get excreted in individuals so the bio acccumulation takes place and when the accumulation exceeds certain limit the ultimate effect can be seen that affects the nervous system. Now you see this the the answers that are right are exceeding these lines. remember that have shrked the question to fit it in the screen. So you know it might look like you know I'm writing too much you know and then it's exceeding it's moving out of the lines but when you write in the actual paper that actually fits here the size is less and that's the reason it looks like it. Let's move to the next question. Okay. So, Jamea investigates the color dyes used to make an ink and to check the amount of dyes. okay, she uses chromatography paper. draws start line in pencil on the chromatography paper. Here's the start line labeled over here. Place the dots of pure dyes on the start line. You can see the red, yellow, green, blue. And then here you see the ink. Place the dots of pure dyes on the strat line. So the ink dot is placed right on here over here. And the other dots of pure dice that is blue, green, yellow and red. And then she puts the chromatography paper in solvent as shown in the diagram. So she'll put this sol inside the solvent that is over here you can see the level of the solvent and she placed this chromatography paper on this. Now she waits until the solvent has moved up the chromatography paper. Now the overall phenomenon is such that this chromatography paper it absorbs this solvent and then so you can see direction of movement of solvent. So this solvent gets absorbed in this paper and slowly slowly slowly slowly the whole solvent moves up and when it moves up it also carries this ink be it pure dice or be it the ink. Now based on the solubility of this dyes of each color as it has different solubility and so based on that you can see the separation that occurs in the zinc. So here if you look at this the pure dyes because they are single colored dyes you can see the solvent when it went above you can see the blue colored is you know is formed over here the green color is over here the yellow is over here red is over here and then ink which is combination of different dyes. So you can see there are three of them. One is over here. The other dot is over here. And the third one is over here. okay. Well well can see that this dot represents that it might be the red one. this dot represents this one. So that's blue dye. And this represents this. So that's green dye. Let's see what's the questions are. So Jamila puts her ink and pure dies on pencil line rather than line drawn with an ink pen. So the line the start line that was drawn it is said that she she used pencil to draw the line rather than ink pen. Well we know if she used an ink pen that ink would again dissolve in the solvent and the reading might not be accurate. So pencil was used. So in the answer I'll write ink will dissolve in the solvent while pencil line while pencil line does Not. Okay. Measure the distance in from the start line to do Now if it was the physical paper, you would use your scale and check what is the the distance of dot from the start line. So from you know from here to here the start line to dot this distance you need to measure with the scale. Now if you had the actual paper it comes around 37 or maybe plus or minus2 arounded value you can make mean based on the measurement it would be somewhat near this 37 plus or minus 2 and distance to solvent front that is this is the solvent front okay over here you have the label so from here to here the distance from the solvent front which is around 42 and plus or minus 2. So that's basically that much uncertaintity is allowed while what measurements you have made in the paper. Now calculate the excuse me the RF value for dot use the equation. The equation says it's the ratio of distance from the start line to do that is this one divided by distance from start line to the solver front that is the other one. So here would use RF is equal to the initial that is let's take it 37 and this is from the start line to the solvent in front S42. So what am getting is 0.88. So RF is 0.8. 88 it's ratio so don't use any unit over here which color dies are present in the ink well now we already discussed this that is ink dot here represents this one and so the pure dye is of red color this one over here represents this one so that's the position relates to blue color and this position relates to the green color so we have red, green and blue color dice present in the ink. So that's it for qu that were question 1 to 7 and now part two as mentioned once it's done I'll be putting the link in the description. If you have any queries, any doubt regarding the whole paper or any question, you can just comment below and definitely we'll get back to you. You can also mail us. And yes, one important thing, if you haven't subscribed yet, please do subscribe and do share it with friends who are preparing for the examination. Also, we are building our website and more free solved content and resources will be available on that. So do check out solguide.com. Thanks lot. See you in the next video.