CBSE Pathshala

CBSE Guess Questions 1 MARKS QUESTIONS 1. What will be the effect of increase in the amount of CO2 in the atmosphere on the average temperature of the earth? 2. Why is it necessary to conserve our environment? 3. Which of the following is the major constituent s of biogas? CO2, H2, CH4, CO 4. Which of the following pollutants of air would affect the capacity of blood in human bodies to absorb O2 from lungs? 5. Where was CHIPKO MOVEMENT started? 6. What will be the result of excess CO2? 7. What are the two major benefits of dams? 8. What are kulhs? 9. List any two traditional systems of water harvesting. 10. How is the increase in demand for energy affecting environment already? 2 MARKS QUESTIONS 1. Write two advantages of classifying energy sources as renewable and non renewable. 2. Why should we conserve forests? Suggest any two ways of con...

QUESTIONS FROM CBSE EXAMINATION PAPERS: 1. What is the role of pupil in a human eye? 2. What is the range of vision of a normal human eye? 3. Name the part of the human eye that helps in changing the focal length of the eye lens. 4. Which coloured component bends the least during the dispersion of white light through prism? 5. Name the part of the eye (a) That controls the amount of light entering into the eye. (b) That has real, inverted image of the object formed on it. 6. A person is advised to wear spectacles with convex lenses. State the defect of vision he is suffering from. 7. Draw a ray diagram to show the angle of deviation when a ray of light passes through a glass prism. 8. When one enters a dim-lit room from bright  light, one is unable to see the objects in the room for some time. Why? 9. What is meant by near point of a human eye? 10. A person is advised to ...

                                 Board Solved Questions Set-01 Q.1. Why does silicon is classified as Metalloid? Ans: Silicon is gray color solid at room temperature with very high melting point and boiling point that lose or gain 4 electrons  [  3s 2 , 3p 2 ] having both metallic and non metallic properties so it is classified as Metalloid eg. Sio 2 Q.2.Why inert gases have zero valencies? Ans: It is because Inert gases have 2 or 8 electrons in valence shell. Q.3. How is valency of an element determined? Ans: The valency of an element measures its ability to combine with other elements. The valency is determined by knowing place in periodic table.. All the elements in group VIII have eight electrons in their outer shells,...

Q.1) Write down the names of compounds represented by the following for mulae: (a)Al 2 O 3                             (b) Ca 3   (PO 4 ) 2  (C)K 2 So 4                                          (d) Na 2 S                                     Q.2) Calculate the number of molecules present in 0.5 mol of water. Q.3) Calculate the mass of one atom of hydrogen atom. Q.4) what is formula mass? Calculate formula mass of NaCl. Q.5) Calculate the number of molec...

9 th Chapter: sound –Guess Questions for practice 1. If you place some small blades on a drum, what will you observe when you beat this drum with a drum stick? Explain. 2. Describe an activity with a (a) metre scale (b) rubber band to show that only a vibrating body produces sound. 3. With the help of tuning fork demonstrate that sound is produced by a vibrating body. 4. What is vibrating in the following musical instruments producing by a musical sound? (a) Violin (b) drum (c) saxophone (d) flute (e) guitar (f) dholak (g) tabla (h) sitar 5. What is medium? What constitutes the medium? 6. Describe an activity to show sound travels faster through a solid medium than through a gaseous medium. 7. Describe an activity to show sound travels faster through a solid medium than through a liquid medium. 8. Describe the experiment to demonstrate that waves do not c...