8 SCIENCE MOST IMPORTANT QUESTION

Q1. DDT is now banned in countries such as India. 1) True 2) False Solution DDT is now banned in countries such as USA but not in India. Q2. Algae are photosynthetic and hence add a large amount of oxygen to the water. 1) False 2) True Solution Algae compete with aquatic organisms for oxygen and deplete the oxygen levels in water bodies. Q3. Industrialisation and rising population are the contributors for global warming. 1) True 2) False Solution True Q4. How does the Indian legal system protect the Taj Mahal from pollution? Solution The Supreme Court of India has ordered industries in and around the Taj Mahal to switch to LPG and CNG. It has...

Q1. Which of the following was the first satellite launched by India? 1) Aryabhatta 2) EDUSAT 3) Kalpana-1 4) INSAT Solution Aryabhatta was the first satellite launched by India. Q2. Which of the following celestial objects separates the inner and outer planets of the solar system? 1) Meteor 2) Asteroid 3) Meteorite 4) Comet Solution Asteroid separates the inner and outer planets of the solar system in the form of the asteroid belt. Q3. How many constellations are officially recognized by the International Astronomical Union (IAU)? 1) 108 ...

Q1. A material that allows light to pass through it without significant distortion is known as 1) Opaque 2) Transparent 3) Translucent 4) Luminous Solution A material that allows light to pass through it without significant distortion is known as transparent. Q2. ___________ reflections are used in periscopes. Solution Multiple reflections are used in periscopes. Q3. We can see an object only when the light may have been 1) Reflected by the object 2) Emitted by the object 3) Absorbed by the object 4) Emitted or reflected by the object Solution It is only when light from an obje...

Q1. What are focus and epicentre of an earthquake? Solution The place inside the earth's crust where the earthquake is generated, is called focus of the earthquake. The point on the earth's surface directly above the focus is called epicentre. Q2. What magnitudes of earthquakes on Richter scale are considered destructive? 1) Higher than 4 2) Higher than 7 3) Higher than 12 4) Higher than 9 Solution The magnitude of earthquakes higher than 7 on Richter scale are considered destructive. Q3. What happens when we touch the metal cap of a charged electroscope with our finger? What is this process known as? Solution The leaves of an electroscope collapse as soon as we touch the metal cap with hand because the leaves of the charged electroscope lose charge t...