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CBSE CLASS CHAPTER NO.15 SOME NATURAL PHENOMENA:Question Banks 1. How many types of charges exist? a. One b. Three c. Two d. Four 2. Who invented the lightning conductor? a. Alexander Fleming b. Graham Bell c. Benjamin Franklin d. Thomas Alva Edison 3. What device is used to protect building from lightning? a. Crescograph        b. Anemometer      c. Lightning Conductor        d. Barometer 4. What scale is used to measure the magnitude of earthquake? a. Richter b. Celsius c. Fahrenheit d. Kilogram 5. The magnitude of earthquakes that occurred at Bhuj and Kashmir were a. less than 4             b. less than 2                     c. less than 6        d. Higher than 7 6. Name two natural phenomena which cause us heavy damage. 7. Why were the people of ancient times afraid of lightning? 8. What is lightning due to? 9. What was the discovery made by Ancient Greeks? 10. List two daily life examples where charges are produced. 11. What are charged objects?

Q. Fill in the blanks (a) The intensity of an earthquake is measure on the -------------   ------------------ Ans: Richter scale (b)------------- is a huge wave due to an earthquake occurring under the sea floor. Ans: Tsunami (c) earthquake are cause because of the motion of the ------- plates in the outer crust of the earth. Ans: Tectonic (d) Shock wave of earthquake are called -------------- Ans Seismic wave (e) An earthquake of magnitude 2-4 on Richter scale is a  ---------------  one Ans: weaker (f) An earthquake of magnitude 8 or more on Richter scale is a  ---------------  one Ans: stronger (g)The instrument used to measure earthquake wave is called --------------. Ans: seismograph (i)The intensity of tremors is highest near the ------------- Ans: fault zone or epicenter (j) The intensity of tremors ----------- with distance from the epicenter. Ans: Spread For full solved answer Visit chemistry adda: Earthquake: Some Natural Phenomenon:C

8th Science Chapter Earthquake:Some natural Phenomenon Q. What is an Earthquake? Ans: An earthquake is a sudden shaking or trembling of the earth lasting for a very short time. Q. What Causes an Earthquake? Ans: Earthquake   is caused by a disturbance deep inside the earth’s crust created by  motion of tectonic plate. Q. What could cause a disturbance inside the earth? Ans: Some time moving tectonic plate goes under another due to collision and cause a  disturbance inside the earth. Q. What are seismic waves? Ans: Waves produce by earth quake on the surface of earth is called seismic waves. Q. Where does the greatest number of earthquakes occur? Ans: The boundaries of the tectonic plates are the weak zones where earthquakes are  more likely to occur. The weak zones are also known as seismic or fault zones. Q. What are different cases of tremors? Ans: Tremors on the earth can be caused when a volcano erupts, or a meteor hits the  eart

Activity based Questions with answer: X Chapter: Carbon and Its Compounds 1. Q. What happen when few drops of alkaline KmNO 4   added to Ethanol? Ans: In the begging color of KmNO4 disappear. When excess KmNO 4   is dissolved in solution colour cannot disappear because whole Ethanol gets oxidized into Ethanoic acid. CH3CH2OH ----- KmNO 4 ------Heat------->CH3COOH Hence, alkaline KmNO 4 or Acidified K2Cr2O7 oxidized alcohol into ethanoic acid 2. Q. How can we convert unsaturated hydrocarbon into saturated hydrocarbon? Ans: By the addition reaction of unsaturated hydrocarbon with halo atom in the presence of catalyst. HC=CH    +H2 -------------Ni--------570 0   K------> Ch3-CH3 R2C=CR2 + H2    ------------Ni---------> R2HC-CHR2 (Vegetable Gee) This reaction is known as Hydrogenation reaction. 3. Q. How can you test that given hydrocarbon is unsaturated? Ans: When few drops of Bromine is added to unsaturated hydrocarbon

7 th Reproduction in plants solved Questions,MCQ,For  Summative   assessments 1.What is meant by reproduction? Ans: The process of producing new individuals of same kind of the same species is called reproduction. 2. Why reproduction is a essential life process? Ans: Reproduction is essential for continuation of the species from generation to generation. 3. What are the different modes of unisexual reproduction? Ans: modes of reproduction evolve only one parent is called unisexual reproduction. (a) Fission: The mode of reproduction in which unicellular organism split into two equal halves and produce new ones is called binary fission. For example amoeba and bacteria (b) Fragmentation: The mode of reproduction in which body of plant breaks up into smaller fragments and each fragment grows into a new individual is known as Fragmentation e.g. Spirogyra , algae (c) Budding: The mode of reproduction in which small buds when develop get separated and mature into new

Download CTET answer key for November 2012 exam conducted on 18.11.2012. The answers are provided by our website users. If you have a different answer, please mail us at onlineteachers@yahoo.co.in or post as comment below this news item. You can discuss any question or any query related to CTET November 2012 exam in this section. We appreciate your comments and discussions. These will definitely help us to serve you better. Download CTET Answer Key Here By http://onlineteachers.co.in/ 

Answer these question 1. Question:  Explain how animals dwelling in the forest help it grow and regenerate. Ans: A nimals in the forest help it grow and regenerate in many ways like:  Animals help in dispersal of sees. Micro organism  supply   nutrients  for growth.   Many seedlings growing in a decaying heap on animal droppings. 2. Explain how forests prevent floods. Ans: Forest absorb rainwater and allows it to seep naturally.its leaves and branches prevent rain to hit the ground directly. 3. What are decomposers? Name any two of them. What do they do in the forest? Ans: The micro-organisms which convert the dead plants and animals to humus are known as decomposers like Fungi and bacteria. They  convert dead leaves and dead animals  into humus 4. Explain the role of forest in maintaining the balance between oxygen and carbon dioxide in the atmosphere. Ans: During respiration plants and animals take in oxygen  and release carbon dioxde. During  photosynthes