Tuesday, February 28, 2017

SSC Papers Science I

SSC Papers for Practice Science I Maharashtra Board
I) A.(a) Rewrite the following statements with suitable words in the blanks: (2)
        i. In ________ combination of resistors, the current is the same in every part of the circuit.
      ii. Nutritional enrichment of water is called________.

I) A.(b) Rewrite the following table so as to match the second column with the first column: (2)
Column ‘A’
Column ‘B’
i)        Natural indicator
a.      Neutralization
ii)      2Cu+O2→2CuO
b.      Beet root
iii)    Synthetic Indicator
c.       Methyl orange

d.      Oxidation
           
I) B. Rewrite the following statements by selecting the correct options: (5)
i) 1 µA = ________ A.
a) 10-3
b) 10-8
c) 106
d) 106
ii) A student added few drops of universal indicator to kokam extract, the colour of the solution will become________.
a) Pink
b) Violet
c) Orange
d) Blue
iii) For spherical mirrors distances measured perpendicular to and above the principal axis are taken as  ________.
a) Negative
b) Zero
c) Positive
d) Infinite
iv) If four resistors having values 1 Ω are connected in parallel combination, the effective resistance will be ________.
a) 2 Ω
b) 0.25 Ω
c) 4 Ω
d) 2 Ω

v) While performing an experiment to trace the path of a light ray through a rectangular glass slab, four students 1, 2, 3 and 4 tabulated their observation as given below:
Students
r
e
1
40
50
55
2
60
40
40
3
40
35
40
4
50
55
50
a) 1
b) 2
c) 3
d) 4

II) Solve any five of the following: (10)
i)  Give any four uses of bleaching powder.
ii) Why do the elements in the same group of periodic table show same valency?
iii) Find the resistance of 60 W, 240 V bulb.
iv) Draw a ray diagram for concave mirror when the object is kept at focus.
v)  Stars twinkle at night. Give scientific reason.
vi) Define the term ‘Redox reaction’. Give one example of it.

III)  Answer any five of the following: (15)
i) Explain the refraction of light when a ray moves from denser medium to rare medium.
ii) Classify following elements into metals, non-metals and metalloids:
B, Mg, O, F, Si, He, Na, Cl, K.
iii) Write a short note on ‘Alternating Current (AC)
iv) Identify ‘X’ and ‘Y’ and write the balanced chemical reaction for the following:
a. When ‘X’ burns in presence of oxygen, the oxide of ‘X’ i.e. Alumina is formed.
b. When Sulphur dioxide gas reacts with hydrogen sulphide gas, sulphur and ‘Y’ are formed.
v)  Describe the effects of soil pollution on ecosystem.
vi) Explain the working of electric iron and bulb.

IV)  Attempt any one of the following: (5)
i)  Describe the construction and working of an A.C. generator.
ii) Priya, a student of standard IX is using spectacle of number -2.0. from this information answer the following questions:
a. Name the defect of eye from which Priya is suffering.
b. Which are the two possible reasons behind this defect of eye?
c. Name the type of lens she is using in her spectacle.
d. Find the focal length of the lens.