TEST PAPER 20 : CHAPTER 6 : ENERGY SOURCES : 25 MARKS

There are 13 questions in all and time limit is 45 minutes.

SECTION - A : CHOOSE APPROPRIATE ALTERNATIVE : [1 mark each, Total marks 3]

1. How much solar energy reaches earth's surface ?
   
   
   
   1. 3.8 x 10²⁴ J/s
   2. 3.8 x 10²⁶ J/s
   3. 1.7 x 10¹⁷ J/s
   4. 1.7 x 10²⁶ J/s
      
   
   
2. The number of carbon atoms in hydrocarbon molecule of kerosene is...
   
   
   
   1. 5 - 8
   2. 8 - 11
   3. 10 - 14
   4. 12 - 16
      
   
   
3. The calorific value of biogas is ______ kJ/g.
   
   
   
   1. 30 - 35
   2. 35 - 40
   3. 40 - 45
   4. 45 - 50
      
   
   

   SECTION - B : ANSWER IN SHORT : [1 mark each, Total marks 3]
   

4. what is the full form of LPG ?
5. What is the benefit of Ocean Thermal Energy ?
6. What is the boiling range of diesel ?
   
   

   SECTION - C : ANSWER IN BRIEF : [2 marks each, Total marks 8]
   

7. How are smokeless chulhas more efficient than the traditional chulhas ?
8. Give reason : The calorific value of wood is lower than that of the hydrocarbons.
9. Explain how the energy obtained from fusion is better than that obtained from fission reactions ?
10. Mention limitations of windmills.
    
    

    SECTION - D : ANSWER THE FOLLOWING : [3 marks each, Total marks 6]
    

11. Explain construction and working of solar cells.
12. Describe an experiment to find the calorific value of wax.
    
    

    SECTION - E : ANSWER IN DETAIL : [5 marks each, Total marks 5]
    

13. What is chain reaction ? Describe ideal conditions to support a nuclear chain reaction.