CBSE ADDA

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