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SUMMATIVE ASSESSMENT – II, 2014 Class – X, SAMPLE PAPER

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Find CBSE class 10th Guess paper for the for 2014 board examination. Question has been framed as per the analysis and facts that came from the previous year question papers Find CBSE class 10th Science Sample paper for the second term examination. Question has been framed as per the syllabus covered in the second term  examination

8th CBSE Chapter-STARS AND THE SOLAR SYSTEM Solved Questions

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 Q1. Define light year. Ans. Light year is the distance travelled by the light in one year. Q2. Name the star nearest to the earth after sun. Ans. Proxima centuari. Q3. Why do stars shine? Ans. Stars are giant ball of gases in space that shine through the darkness and are held together by the force of gravitation. These gasses are hydrogen and helium. Some of the hydrogen is converted into  helium. A star shines due to this reaction nit’s core releasing energy that radiates into the outer space. Q4. What are constellations? Ans. Group of stars that make an imaginary shape in the night sky is called constellations. There are 88 constellations known so far. Examples ursa major, Ursa Minor, Orion, Aries cancer, Cassiopeia, Gemini,  Leo. Q5. Write short note on pole star. Ans. Pole star rises in the east at night and sets in the west in the early morning. Pole star is situated above the axis of rotation of the earth, so it appears stationary from the earth. So it is u

Derivation of Lens and mirror formula X Reflection and Refraction of light

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MIRROR FORMULA The relation between object distance(u), image distance(v) and the focal length (f) of the mirror is known as MIRROR FORMULA. Consider a concave mirror MM' (of small aperture). An object AB of height h is placed on the left of the mirror beyond its center of curvature so that the image formed is real, inverted and diminished in size(height = h'). Here : Object distance = PB = -u Image distance = PB'= -v Focal length = PF = -f Radius of curvature = PC = -R As shown in Figure, Δ ABP ∼ Δ A'B'P. ∴ A'B'/AB = PB'/PB ∴ A'B'/AB = (-v)/(-u) ∴ A'B'/AB = v/u.............(I) Similarly, as shown in the figure, Δ ABC ∼ Δ A'B'C. ∴ A'B'/AB = CB'/CB ∴ A'B'/AB = (PC-PB')/(PB-PC)........[as CB'=(PC-PB') and CB=(PB-PC)] ∴ A'B'/AB = [-R - (-v)]/[-u - (-R)] ∴ A'B'/AB = (-R + v)/(-u + R)........(II) By (I) & (II), v/u = (-R + v)/(-u + R) ∴ -

Multiple choice questions in science for class VII as per NCERT Text Book

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Nutrition in plants 1.      The components that are necessary for our body are called (   ) a.      Vitamins b.      Pulses c.         Nutrients d.      Minerals 2.      The mode of nutrition in which organisms make food themselves from simple substances is called(   ) a.        Autotrophic nutrition b.      Heterotrophic nutrition c.       Saprotrophic nutrition d.      All of the above 3.      Some organisms live together and share shelter and nutrients. This is called a.      Predation b.        Symbiotic relationship c.       Autotrophs d.      Heterotrophs 4.    The bacterium which provides nitrogen to the leguminous plants is a.        Rhizobium b.      Yeast c.       Fungi d.      Lichens 5.      Pitcher is an example of a.        Insectivorous plant b.      Leguminous plant c.       Algae d.      Fungi 6.      The process by which a plant prepares its food  “Photosynthesis” takes place in the presence of  (   ) a.      Moo