रवि  मोहन
X
Science (Theory)
Time – 2.30                                                                                            Max.Marks - 60
General  Instructions :-
The question paper comprises of two sections A and B. You are to attempt both the sections.
All questions are compulsory.
 There is  no  overall  choice.  However  internal  choice  has  been  provided  in  the  some  questions.  You  are  the  attempt  only  one  options  in  such  questions .
You   are  advised  to  attempt  all  the  question  of  section     A  and  section  B  separately.
Questions number 1-6 in section A and 17-19 in section B are very short answer questions and carry one marks each        
Question  number  7-10  in  section A and 20-24 in  section  B  are  short  answer questions and carry two marks each.
Question  number  11-14  in  section A and 25-26 in  section  B  are  short  answer questions and carry three marks each.
Question number 15 and 16 in section A and 27 in section B are short answer questions and carry five marks each.
                                                 
                                        SECTION-A
1.  If  the  magnification  of  a  body  of  size   1m is 2. What is the size of the image?     
2.  What do you mean by “rancidity”?                                                                               
3.  what  is  double  the   amount  of   gas v collected  in  one  of  the  test  tubes  on       electrolysis   of  water  ?  Name this   gas.                                                                          4.  Name the most metallic and most non- metallic element in the periodic table.   
5.  Name an acid base indicator prepared at home.                                                                    6. What is meant by the statement that “potential difference between points A & B in an   electric field is 1 Volt”?                                                                                                    
7. How  many  176      resistors  (in  parallel)  are   required   to  carry  5A in  220  V  line?                                                                                                                                      
8. Why should curd and sour substance not be kept in brass and copper vessels?                                                                                                                   
9. Two  electric  lamps   of  100 W  and  25W  respectively   are  joined  in  parallel  to  supply  of  200 V  calculate  the  total  current  flowing   through  the   circuit .              
10. What happens when aluminium metal reacts with sodium hydroxide? Give the equation for the chemical reaction?                                                                                   
11. Describe  with  the  help  of  a  labeled  diagram  the  method   of  refining  of  metals   by  electrolytic   method  taking copper  as  an example.                                     
12. Here  are  given  some  elements    belonging  to  a  specific  group  and  period  in the  periodic  table
          Li           Be        B       C         N      O      F             Na          Mg       Al      Si        P       S       Cl
    Give  answer:
(i)   Which   is   more   reactive    between F & Cl?
(ii)  The   most  metallic  and  the  most  non-metallic  element.
(iii)  Element  of  smallest  atomic  size  and  the  element  of largest  atomic  size?          13.  A concave mirror of   focal length 15 cm.   forms  and  image  of  an  object  kept  at  a  distance  of  10 cm. from  the  mirror  .  Find the position, natural and size of   image formed by it.                                                                                                    
14. Give three advantages of nuclear   fusion   process over nuclear fission   to generate   electricity.                                                                                                            
15. What is ohm’s law?   Light    an experiment   to verify ohm’s law.                           
                                                 Or 
What is solenoid? Draw the magnetic field lines due to a current carrying solenoid.    Write some properties of magnetic   field lines…
16.        Explain  the  following  terms  with  suitable  examples:                                        
    (a) Oxidation (b)Reduction (c) Oxidizing agent (d) Reducing agent   (e) chemical equation    
                                               Or
   Define pH. Explain the role of pH in every day life.
                                  SECTION - B
17. Give an example of a vestigial    organ present in human.                                          
18. What is a food   chain?                                                                                                
19. Where does fertilization takes place in the human beings?                                         
20. What is the roll of decomposers   in an ecosystem?                                                       
21. What are fossils?  what  do  they  tell  us  about  the  process  of  evolution  ?          
22. Write the cause of depletion of ozone layer in the atmosphere.                                   
23. How does intestinal juice contribute to the digestion of proteins?
24. Describe double fertilization in plant.                                                                           
25. Draw   a  well  labeled  diagram  of  the  longitudinal  section   of  a flower  and       briefly   write  about  its  sexual  whorls . 
26. Define reflex action with suitable examples.
27. (a) Name the blood groups under ABO system.
      (b) Differentiate between universal donor and universal recipient under this system.
                                                            Or
       Explain the human digestive system with the help of a diagram.
                  
                                    
 
 
 
