SECTION - A
Q.1. (A) Rewrite the following statements by selecting the correct options : 5 marks
(i) To increase the effective resistance in a circuit the resistors are
connected in ..................... .
(a) series (b) parallel (c) series and parallel (d) none of these
(ii) The phenomenon of splitting of light into its component colours is
..................... .
(a) reflection (b) refraction (c) dispersion (d) rectilinear propagation
(iii) The phenomenon of change in the ..................... of light when it
passes from one transparent medium to another is refraction.
(a) wavelength (b) frequency (c) direction (d) amplitude
(iv) Turning back of light from the surface on which it falls is called
..................... .
(a) refraction (b) reflection of light (c) dispersion (d) rectilinear propagation
(v) In India, the frequency of A.C is ..................... cycles per second.
(a) 50 (b) 100 (c) 60 (d) none
Q.1 (B) Fill in the blanks : 1
(i) The arrangement of elements in a group of three is called ...............
Q.1 (C) State the true or false : 1
(i) A substance having pH value 7 will have effect on litmus paper.
Q.2. Answer the following sub questions : 6
(i) State the function of iris and ciliary muscles.
(ii) Connecting wires in a circuit is made of copper and aluminium. Why ?
(iii) Baking soda (sodium hydrogen carbonate) reacts with dilute hydrochloric acid. (Write balance chemical reaction)
Q.3. Answer ANY FOUR of the following questions : 12
(i) Explain how formation of rainbow occurs.
(ii) Explain the importance of pH in everyday life.
(iii) (a) Distinguish between : Periods and Groups.
(b) Define Dispersion of light.
(iv) (a) Distinguish between Electric motor and Electric generator.
(b) Define magnetic field
(v) Draw a ray diagram for object position between F1and O of a convex
lens.
Q.4. Answer ANY ONE of the following questions : 5
(i) (a) Write a short note on Dispersion of light.
(b) Light travels from rarer medium to denser medium. If the angle
of incidence is 30º can the angle of refraction be 41º. Why ?
(ii) (a) State the characteristics of connecting resistances in parallel.
(b) Why tungsten wire is not used in electric fuse ?
SECTION - B
Q.5. (A) Fill in the blanks : 3
(i) The digested food is absorbed by the ....................... in the small
intestine.
(ii) ....................... is the largest gland in the body.
(iii) The valency of aluminium is ....................... .
Q.5. (B) Name the following : 2
(i) Maintenance of steady state by different systems in an organism.
(ii) The small gap between the consecutive neurons.
Q.5. (C) Answer in one sentence : 1
(i) Name the metals that are the poor conductors of heat.
Q.5 (D) State the true or false : 1
(i) Ethylene contains carbon carbon triple bond.
Q.6. Answer the following questions : 6
(i) In human beings the gamete from the male parents decides the sexof the baby. Why ?
(ii) Iron filings are sprinkled in the flame of the burner.
(Write balance chemical reaction)
(iii) Write a note on connecting links.
Q.7. Answer ANY FOUR of the following questions : 12
(i) Explain Darwin's theory of evolution.
(ii) How are fats digested in the human body ?
(iii) Explain co-ordination in plants.
(iv) Write a note on blood pressure.
(v) Explain the properties of ionic compounds.
(vi) (a) Distinguish between : Diamond and Graphite.
(b) Name a metal that forms amphoteric oxide.
Q.8. Answer ANY ONE of the following questions : 5
(i) Explain how food is digested in the small intestine.
(ii) Describe sexual reproduction in plants.