Science Olympiad Model Test Paper - 3 | Science Olympiad Class 9 PDF Download

Ans: (b)
The mirror image is always laterally inverted means the left side of the object, when seen in the mirror, is on the right side and vice versa.

Ans: (a)

• First, we analyze the first row: 168 (even) divided by 14 (even) gives us 12.
• Next, we take 12 (even) and apply the last rule with 1525 (odd): 12 + 1525 = 1537.
• Now, for the second row: 25 (odd) and 10 (even) means we add them: 25 + 10 = 35.
• Finally, we see that the first row's result is 12, and the second row's result is 35, but we need to find the resultant based on the first row's operations.
• Thus, the answer is 42, as it follows the rules correctly.

Ans: (b)
Each number in the series is 2 less than thrice the preceding number.
So, missing number = (10 x 3) - 2 = 28

Ans: (a)
P = 7, A = 4, I = 1, N = 2, T = 8
E = 9, X = 3, C = 5, E = 9, L = 6
So, in A C C E P T. A is coded as 4, C as 5, E as 9, P as 7, and T as 8. Hence, the correct code for ACCEPT is 455978.

Ans: (c)
Person’s father = Only son of woman’s daughter’s grandfather’s husband’s = Woman’s husband.
So, he is the son of the woman.

Ans: (a)
All other figures contain a geometrical figure along with its mirror image.

Ans: (c)
In each step, one of the elements gets laterally inverted.

Ans: (c)
Figure 4, is the correct water image of the word F A M I L Y.

Ans: (d)
Only in fig. (4), the black triangle and the black circle lie at the two ends of the same diameter.

Ans: (a)

• Komal starts at her house and walks 20 m North.
• After turning right, she walks 24 m East.
• Then, she turns right again and walks 27 m South.
• To find her final position, we calculate her total movement: she is now 25 m away from her house in the South-East direction.

Ans: (b)
Among the following Phylum Porifera consists of various animals that are non-motile. They are attached to a solid substratum

Ans: (c)

• Statement 1 is true because tin is indeed electroplated onto iron to make food cans, providing a protective layer.
• Statement 2 is false as tin is actually less reactive than iron, which means it does not corrode as easily.
• Thus, the correct option is that only statement 1 is true while statement 2 is incorrect.
• This leads us to the conclusion that the answer is (c).

Ans: (a)

• The asteroid belt is indeed located between Mars and Jupiter in our solar system, making option (a) correct.
• Option (b) is incorrect because hydrogen, not oxygen, is the primary fuel for stars.
• Option (c) is misleading as the inner planets (Mercury, Venus, Earth, and Mars) have relatively few moons.
• Option (d) is false; Mars is called the red planet due to its iron oxide (rust) surface, not because it is the hottest planet.

Ans: (b)
Hepatitis targets liver. It leads to inflammation of the liver tissue.

Ans: (b)

• The question asks for an option that represents a line in a diagram.
• Among the options, Line is the only one that directly indicates a straight path.
• Other shapes like Circle, Triangle, and Square do not represent a line.
• Thus, the correct answer is (b) Line, as it is the only option that fits the description.

Ans: (c)
An athlete runs before jumping to gain momentum. Because it helps in jumping higher and longer because of inertia of motion gained due to the motion.

Ans: (b)
A is paramecium and B is amoeba. As both are unicellular protozooans, they do not possess cell wall. Both of them have heterotrophic mode of nutrition. Amoeba does not cause malaria. Malaria is caused by Plasmodium.

Ans: (a)

• The spring applies equal and opposite forces on both toy carts due to Newton's third law.
• The masses of the carts are 5 kg and 10 kg, which means they will move in opposite directions.
• Their velocities will be in an inverse ratio to their masses, meaning the lighter cart (5 kg) will move faster than the heavier cart (10 kg).
• This is because the same force causes a greater acceleration in the lighter cart, resulting in their velocities being in the inverse ratio of their masses.

Ans: (a)
Plant tissues in which cells keep on dividing are called meristematic tissue.
Meristematic tissues are present in those parts of plants which keep on growing. A meristem is the tissue in most plants containing undifferentiated cells (meristematic cells), found in zones of the plant where growth can take place. Meristematic cells give rise to various organs of the plant and keep the plant growing.

Ans: (d)

• Gravitational attraction causes both particles to accelerate towards each other.
• According to Newton's third law, the forces acting on both particles are equal in magnitude but opposite in direction.
• The acceleration of each particle is inversely proportional to its mass, meaning that the larger mass (m₁) will have a smaller acceleration compared to the smaller mass (m₂).
• Thus, the acceleration of m₁ is proportional to m₂, confirming that option (d) is correct.

Ans: (a)

• The object starts from rest and accelerates constantly over time t.
• In the first half of the time, it covers a distance x₁, and in the second half, it covers x₂.
• Due to the nature of constant acceleration, the distance covered in the second half is greater than in the first half.
• Mathematically, it can be shown that x₂ is three times x₁, hence x₂ = 3x₁.

Ans: (c)

• Rusting of iron is a process where iron reacts with oxygen and moisture, forming iron oxide, commonly known as rust. This is a chemical change because it results in a new substance.
• The other options involve physical changes: melting ice and boiling water change states but not the substance itself, while dissolving sugar in water is reversible and does not create a new substance.
• In summary, rusting is irreversible and alters the chemical composition, making it a clear example of a chemical change.

Ans: (a)
Seed leaves: Cotyledons are called seed leaves as the seeds germinate; cotyledons are the 1st leaves produced by the plants. But they are not true leaves as they are part of the seeds.
Amphibians of the plant kingdom: Bryophytes are called amphibians of the plant kingdom because they require water for fertilization even if they live on land.

Ans: (b)

• Law of constant proportions states that a chemical compound always contains its component elements in fixed ratio by mass.
• In Experiment 1, the mass of copper oxide produced is consistent with the mass of copper used, showing a fixed ratio.
• Experiment 2 also supports this by showing a specific mass of copper obtained from a known mass of copper oxide.
• These results illustrate that the composition of copper oxide remains constant, aligning with the law.

Ans: (c)
In a eukaryotic cell, apart from the plasma membrane, the nuclear membrane and the membrane of mitochondria and plastids are double layered.

Ans: (b)
When bones are dislocated, the muscles and tendons get torn or traumatised

Ans: (c)

• Statement 1 is true because in fractional distillation, the temperature indeed decreases as you move up the column. This allows different fractions to separate based on their boiling points.
• Statement 2 is false because while lower boiling point fractions do condense higher up, the statement implies a direct relationship that isn't accurate in this context.
• Thus, the correct choice is that only statement 1 is true and statement 2 is false.

Ans: (a)
Graph shown in (A) represents uniform motion of an object. A body is said to have uniform motion if it travels equal distances in equal intervals of time.
Graph shown in (B) represents non-uniform motion of an object. A body is said to have non-uniform motion if it travels unequal distances in equal intervals of time.

Figure (C) represents zero displacement. Displacement can be zero even if the distance is not zero. For example, when a body is thrown vertically upwards from a level A on the ground and after some time it returns to the same level A, then the displacement of the body is zero but the distance travelled by the body is not zero.

Ans: (a)
Gravitational force between the two masses is independent of the medium in between them.
So F' = F

Ans: (a)
A cell is capable of independent existence and can carry out all the functions which are necessary for a living being. A cell carries out nutrition, respiration, excretion, transportation and reproduction.  

Ans:(b)
Protein is a macromolecule made up of monomeric units called amino acids.

Ans: (c)

• The sample contains 0.25 mol of sulfur molecules.
• Each molecule of sulfur (S8) contains 8 atoms, so the number of moles of sulfur atoms is 0.25 mol × 8 = 2 mol.
• The number of sulfur molecules is 0.25 mol, which is equivalent to 1.5 × 10²³ molecules (using Avogadro's number, 6.022 × 10²³).
• The total number of sulfur atoms is 2 mol × 6.022 × 10²³ = 1.2 x 10²⁴ atoms.

Ans: (a)
The outer ear consists of a flap like structure called pinna and it is further connected to the ear canal. The pinna collects the sound wave and then directs them through the ear canal. The sound wave on striking the eardrum vibrates it exactly the same way as a sound emitting object vibrates.

Ans: (a)
The rate of diffusion depends on the kinetic energy of the particles.
Since the molecules in the gaseous state possess the highest kinetic energy, they exhibit the highest rate of diffusion.
Kinetic energy of the molecules in the solid state is the least and hence, the rate of diffusion is the slowest in case of CuSO₄ crystal.

Ans: (a)
The time for the sound to travel to the prey and back is 0.2 s, so the time for one-way travel is:
Time (t) = 0.2 s / 2 = 0.1 s.
The distance to the prey can be calculated using the formula:
Distance = Speed × Time = 340 m/s × 0.1 s = 34 m.

Ans: (c)
Genetic mutations and small changes in DNA that affects the normal functioning of the organism. It is genetically inherited and non-communicable.

Ans: (b)

• Soil X has a low amount of silt and clay, making it unable to retain water, which is typical of sandy soil.
• Soil Y is described as poorly aerated but retains a lot of water, indicating it is clayey soil, which is good for crops like paddy.
• Soil Z is porous and has excellent water retention, which is characteristic of loamy soil.
• Thus, the correct identification is that Soil Y is indeed clayey soil, making option (b) the right choice.

Ans: (b)
Chlorofluorocarbons (CFCs) are nontoxic, nonflammable chemicals containing atoms of carbon, chlorine, and fluorine.

They are chemically inactive and do not dissolve in rain water. Hence, they are not removed from the air and reach the stratosphere over a period of time.

Ans: (a)
Gravitation is movement, or a tendency to move, towards the center of gravity, as in the falling of bodies towards the Earth.  

Ans: (c)

• Vacuole is the correct answer because it is the organelle responsible for storing and regulating water within the cell.
• In plant cells, like those in onion peel, vacuoles can be quite large and help maintain turgor pressure, which is essential for keeping the cell firm.
• When there is excess water, the vacuole can store it, thus helping in the elimination of surplus water.
• Other organelles like the nucleus and mitochondria have different functions, such as controlling cell activities and energy production, respectively.

Ans: (a)
Lysosomes are membrane-bound organelles that store various hydrolytic enzymes. They are the site where various unwanted substances, cell organelles and foreign bodies get dissociated. The enzymes stored inside the lysosome comes from the endoplasmic reticulum.

Ans: (b)
The wave frequency can be calculated as:
Frequency (f) = Number of waves / Time = 15 / 3 = 5 Hz.
The wavelength (λ) is the distance between two consecutive crests, so in this case, the wavelength is 2 cm.
Now, wave speed (v) is given by the formula:
v = f × λ
v = 5 Hz × 2 cm = 10 cm/s.

Ans: (a)
Smooth Endoplasmic Reticulum are the organelles responsible for the synthesis of lipids in a cell. Hence, the cells of oil seeds will have greater number and higher activity of SER.

Ans: (b)
Fractional crystallisation is the process of separating the components of a solution on the basis of their different solubilities in the same solvent.
On cooling a solution containing both the solutes, the less soluble component crystallises out first.

Ans: (a)
Yellow fever is caused by a virus. Yellow fever is a viral infection transmitted by a bite from infected mosquitoes most commonly found in parts of South America and Africa. When transmitted to humans, the yellow fever virus can damage the liver and other internal organs and be potentially fatal.  

Ans: (a)

Ans: (c)
Triatomic molecules are molecules composed of three atoms.
Carbon monoxide is diatomic: CO.
All the other options are triatomic.
Ozone: O₃
Carbon dioxide: CO₂
Nitrous oxide: N₂O

Ans: (a)
The distance traveled by boys is ( velocity of boy X time ) + (1/2)at²
Horizontal distance traveled by boy = ( velocity of boy X time )
Difference is distance = ( velocity of boy X time ) + (1/2)at² - ( velocity of boy X time )
= (1/2)at²
= (1/2)²(1)²
= 1 m
The distance traveled by boy is 1 m more than the ball hence, the ball will fall 1m behind the boy.

Ans: (a)
Soda water has dissolved CO₂, which fizzes out when the bottle is opened. This is because the solubility of a gas is directly proportional to the pressure and so, the bottles are sealed under pressure. As soon as the pressure is released, the dissolved gases escape causing effervescence. Hence, CO₂ fizzes out and spreads into the atmosphere.  

Ans: (c)
Collenchyma cells have thin primary walls with some areas of secondary thickening. Collenchyma provides extra structural support, particularly in regions of new growth.
Sclerenchyma provides the main structural support to a plant.