Science Olympiad Previous Year Questions - 3 | Science Olympiad Class 4 PDF Download

Ans: (b)

• The pattern starts with the number 2.
• Each number is multiplied by 3 to get the next number: 2 × 3 = 6, 6 × 3 = 18.
• Continuing this, 18 × 3 = 54.
• After 54, the pattern continues: 54 × 3 = 162, and 162 × 3 = 486.
• Thus, the missing number in the sequence is 54.

Ans: (c)

• To decode the word YARDS, we first need to understand how the letters correspond to numbers in the given examples.
• From START: S=9, T=2, A=1, R=8, T=2. From DAYS: D=4, A=1, Y=5, S=9.
• Using this pattern, we find Y=5, A=1, R=8, D=4, S=9 for YARDS.
• Thus, YARDS translates to 51849, which matches option (c).

Ans: (c)

Ans: (b)
Time shown on the clock is 5: 15 Since, clock is 45 minutes slow, so the correct time will be 6'Oclock. Time after half an hour will be 6 : 30.

Ans: (d)

• Today is Friday because if the day after tomorrow is Sunday, then tomorrow is Saturday.
• Counting from Friday: Today (1), Saturday (2), Sunday (3), Monday (4), Tuesday (5), Wednesday (6), and Thursday (7).
• Thus, the seventh day from today is Thursday.
• So, the correct answer is (d) Thursday.

Ans: (a)

• Pluto was officially reclassified as a dwarf planet by the International Astronomical Union.
• This change occurred on August 24, 2006, marking a significant shift in how we categorize celestial bodies.
• The decision was based on new criteria that defined what constitutes a planet.
• Pluto no longer met these criteria, leading to its new classification.

Ans: (c)

• Both butterflies and houseflies undergo a life cycle that includes four stages: egg, larva, pupa, and adult.
• However, only butterflies lay their eggs in specific environments, often on plants, while houseflies typically lay eggs in decaying matter.
• Both insects can only fly when they reach the adult stage, making statement (iii) true for both.
• Thus, the correct answer is (i) and (iii) only, as they share the four stages and the ability to fly as adults.

Ans: (c)

• The large intestine plays a crucial role in the digestive process by absorbing water from the undigested food.
• While digestion begins in the stomach and continues in the small intestine, the large intestine's main function is to reclaim water.
• Options (a) and (b) are incorrect because the stomach also breaks down proteins, and digestion is not completed in the large intestine.
• Option (d) is misleading as the small intestine does act on proteins, but it is not the first step in digestion.

Ans: (d)
Carbon dioxide is a gas which does not have fixed shape and volume.

Ans: (b)
Melting is the process when a solid converts into liquid.

Ans: (a)

• Inserting and removing a plug into a socket requires you to push the plug in and pull it out, making it a clear example of a combination of forces.
• When you insert the plug, you are pushing it into the socket, and when you remove it, you are pulling it out.
• Other options like ringing a doorbell or squeezing toothpaste do not involve both actions simultaneously.
• Thus, the correct answer is (a) as it perfectly illustrates the concept of using both pushing and pulling forces.

Ans: (C)

• Statement (i): CNG is a cleaner fuel compared to petrol, making it preferable for reducing pollution.
• Statement (ii): Biodegradable wastes can indeed be broken down by microorganisms, so this statement is false.
• Statement (iii): Afforestation actually helps to reduce soil erosion, not increase it, making this statement false as well.

Ans: (a)
Evaporation is the process whereby water evaporates to form water vapours.

Ans: (a)
Molecules are formed by combination of atoms.

Ans: (b)
Water boils at 100°C and freezes at 0°C.

Ans: (b)

• Kettuvallams are traditional houseboats that are primarily found in Kerala, a state in India known for its backwaters.
• These boats are made from coir (coconut fiber) and wood, showcasing the unique craftsmanship of the region.
• While other states like Maharashtra, Gujarat, and Goa have their own water transport, Kettuvallams are specifically associated with Kerala.
• They are popular among tourists for backwater cruises and experiencing the scenic beauty of Kerala.

Ans: (b)

• This experiment demonstrates that soil contains water. When heated by the sun, the moisture in the soil evaporates and then condenses on the cooler lid, forming droplets.
• The presence of water is essential for plant growth and is a key component of soil.
• Other options like air, humus, and fertilizer do not directly cause the formation of water droplets in this scenario.
• Thus, the correct answer is that the soil contains water.

Ans: (d)

• Sea breeze occurs when the air over the land heats up more quickly than the air over the water.
• This causes the air above the land to become warmer and rise, creating a low pressure area.
• Meanwhile, the air over the sea remains cooler, leading to a high pressure area.
• The cooler air from the sea then moves in to replace the rising warm air, resulting in a breeze from the sea.

Ans: (a)
Gases can be compressed maximum and liquids to some extent only, but solids cannot be compressed.

Ans: (a)

• A cuttlefish does not have spines; instead, it has a soft body and uses its color-changing ability for camouflage and communication.
• The yolk of a hen's egg is indeed a source of nutrition for the developing embryo.
• Siberian cranes migrate to India to avoid the harsh winter conditions in Siberia.
• Head lice are classified as ectoparasites because they live on the outside of their host, feeding on blood.

Ans: (b)
Rest three are the forces that are applied against the gravitational force of the Earth.

Ans: (a)
The friction force is the force that acts opposite to the direction of the applied force.

Ans: (d)
We use muscular energy to move our body parts and to lift objects.

Ans: (a)
Magnetic substances like iron and steel are attracted by magnets.

Ans: (a)
Force is a push or pull to change the matter or its properties.

Ans: (b)
The gravitational force of the earth pulls every free object towards the Earth.

Ans: (c)
Plants use solar energy to make food and grow.

Ans: (d)
An electric heater converts electrical energy into heat and light energy.

Ans: (b)
Force is applied to change state of motion of an object.

Ans: (c)

• Initially, a bar of chocolate had a definite shape. This is true as chocolate is solid and maintains its form.
• After 2 hours, the shape of the chocolate changes, but the state remains solid. This statement is incorrect because the chocolate melts, changing its state from solid to liquid.
• The state to which the chocolate changes after 2 hours will not have a definite shape. This is correct as melted chocolate takes the shape of its container.

In conclusion, the correct options are (i) and (iii) only, which is why the answer is (c).

Ans: (c)
Sir Isaac Newton discovered gravitational force when an apple fell on his head while he was sitting under an apple tree.

Ans: (b)
The fans of wind mills are attached to turbines. When wind moves the fans the turbines move to generate electricity.

Ans: (b)
Solar panels store energy during day and use energy at night.

Ans: (a)
The force makes an object to move from its place and the friction is an opposite force that stops the object.

Ans: (b)
In all other cases, the object is said to be in motion.