Science
Science is the systematic study of the natural world through observation, experimentation, and analysis. It involves forming hypotheses, conducting experiments, collecting data, and analyzing results to develop conclusions and theories. The primary aim of science is to understand how the universe works, from the smallest particles to the vastness of space.
Science is divided into several branches:
- Physical Sciences – These include physics, chemistry, astronomy, and geology, and they focus on understanding the laws of matter and energy.
- Life Sciences –These focus on living organisms and include fields like biology, ecology, and medicine.
- Social Sciences – These study human behavior and societies, such as psychology, sociology, and economics.
- Environmental Science –The study of the environment and the impact of human activity on it.
Scientific discoveries and advancements often lead to new technologies that improve our quality of life. Science helps answer fundamental questions about existence, provides solutions to real-world problems, and drives progress in many areas of life.
Question related to Science
- State the factors on which strength of magnetic field at a point due to a current carrying conductor depends?
- Give reasons (a) Platinum, gold and silver are used to make jewellery. (b) Sodium, potassium and lithium are stored under oil. (c) Aluminium is a highly reactive metal, yet it is used to make utensils for cooking. (d) Carbonate and sulphide ores are usually converted into oxides during the process of extraction.
- If all the waste we generate is biodegradable, will this have no impact on the environment?
- How many atoms are there in exactly 12 g of carbon?
- An object of mass 1 kg travelling in a straight line with a velocity of 10 m/s collides with and sticks to a stationary wooden block of mass 5 kg. Then they both move off together in the same straight line. Calculate the total momentum just before the impact and just after the impact. Also, calculate the velocity of the combined object.
- The image formed by a concave mirror is observed to be virtual, erect and larger than the object. Where should be the position of the object? (a) Between the principal focus and the centre of curvature (b) At the centre of curvature (c) Beyond the centre of curvature (d) Between the pole of the mirror and its principal focus.
- What is meant by a substance?
- What do you mean by a precipitation reaction? Explain by giving examples.
- What are plant hormones?
- Why do stars twinkle?
- Why is Tyndall effect shown by colloidal particles? State four instance of observing the Tyndall effect.
- What are the various energy transformations that occur when you are riding a bicycle?
- What is a spectrum? How can we recombine the components of white light after a glass prism has separated them?
- In what direction does the buoyant force on an object immersed in a liquid act?
- A stone is released from the top of a tower of height 19.6 m. Calculate its final velocity just before touching the ground.
- Why are carbon and its compounds used as fuels for most applications?
- Why do ionic compounds have high melting points?
- What type of oxides are formed when non-metals combine with oxygen?
- The distance between two stations is 240 km. A train takes 4 hours to cover this distance. Calculate the speed of the train.
- Find the power of a concave lens of focal length 2 m.
- Why does the sun appear reddish early in the morning? Will this phenomenon be observed by an astronaut on the Moon? Give reason to justify your answer.
- What are alloys?
- Write the names of the product formed when zinc reacts with NaOH. Also write the balanced chemical equation for the reaction involved. Write a test to confirm the presence of the gas evolved during this reaction.
- In the following example, try to identify the number of times the velocity of the ball changes: “A football player kicks a football to another player of his team who kicks the football towards the goal. The goalkeeper of the opposite team collects the football and kicks it towards a player of his own team”. Also identify the agent supplying the force in each case.
- Which of the following constitute a food-chain? (a) Grass, wheat and mango (b) Grass, goat and human (c) Goat, cow and elephant (d) Grass, fish and goat
- State two ways to prevent the rusting of iron.
- Which organisation approves the names of elements all over the world ? Write the symbol of gold.
- Which of the following is the smallest unit of matter?
- What are anhydrous and hydrated salts? Explain with a suitable example of each.
- How much momentum will a dumb-bell of mass 10 kg transfer to the floor if it falls from a height of 80 cm? Take its downward acceleration as 10 m/s².