# SSC – GS Physical Sciences EM Model Paper 1

SSC Public Examinations, March
General Science Paper-I (Physical sciences)
Part - A and B (Time: 2 1/2 hours Max. Marks: 50)

Part- A (Time: 2 hours - marks: 35)

Section - I

Note: 1. Answer any FIVE questions from the following. 2. Each question carries TWO marks. 5 × 2 = 10

Group - A
1. Write differences between Geo-centric theory and Helio- centric theory.
2. A stone moving along a circular path makes 20 revolutions in 10 seconds. What is the angular velocity of the stone?

3. Define a) Solid angle b) Candela
4. Give examples for a) Ohmic conductors b) Non ohmic conductors.

Group - B
5. What are the defects of Rutherford model?
6. State the following laws: a) Mendeleev's periodic law b) Doberiener's law of triads.
7. 20 ml of alcohol is mixed with 160 ml of water. Find out volume percentage of this solution.
8. Draw the structures of a) Benzene b) Paracetemol.

Section - II . Note: 1. Answer any FOUR questions among the following. 2. Each question carries ONE mark. 4 × 1 = 4

9. What is the function of a photo- cell in a TV camera
10. Give examples for Isotopes.
11. Find the magnetic moment of a magnet of length 5 cm and pole strength 2 × 10-3 Amp.metre.
12. The [H+] ion concentration of a solution is 0.00001M. Find its pH.
13. What is denatured spirit?
14. Draw the structure of Aniline Yellow dye.

Section - III

Note: 1. Answer any FOUR questions choosing at least TWO from each group. 2. Each question carries FOUR marks. 4 × 4 = 16

Group - A
15. Write differences between centripetal force and centrifugal force.
16. Derive 1/R = 1/R1 + 1/R2 + 1/R3
17. How do you find velocity of sound in air experimentally by using resonating air columns?
18. Explain the formation of p - type semiconductor and n - type semiconductor.

Group - B
19. Explain the formation of co-ordinate covalent bond with an example.
20. A gaseous mixture contains 4 grams of Hydrogen (mol.wt = 2) and 168 grams of nitrogen
(mol.wt = 28). Calculate the mole fractions of Hydrogen and Nitrogen.
21. How is soap manufactured industrially?
22. Classify drugs depending upon the therapeutic action?

Section - IV

Note: 1. Answer any ONE of the following questions. 2. This question carries FIVE marks. 1 × 5 = 5
23. Draw a neat diagram of Screw gauge and label its parts.
24. Draw a neat diagram to show manufacture of alcohol industrially and label its parts.

Part- B (Time: 30 Minutes Marks: 15)

Note: 1. Answer all the questions. 2. Each question carries 1−2 mark.

I. Multiple choice questions.

1. A very sensitive instrument among the following is [ ]
A) Metre scale B) Vernier callipers C) Measuring tape D) Screw gauge

2. A cricketer throws a ball vertically upwards and catches it 3.0 sec. later. Neglecting air resistance, find the speed with which the ball leaves his hand. [ g = 10 m/s2] [ ]
A) 10 m/s B) 15m/s C) 20m/s D) 5 m/s

3. SI unit of centripetal force is [ ]

4. The luminous intensity of a point source is 5 candela. The total luminous flux through a solid angle 10 steridians is [ ]
A) 50 lumens B) 2 lumens C) 1−2 lumen D) 15 lumens

5. The radio active decay constant λ = [ ]
A) 0.963/T B) 0.693/T C) 0.396/T D) 0.639/T

6. SI unit of Plank's constant is [ ]
A) erg.sec B) erg/sec C) Joule.sec D) Joule/sec

7. Uranium is [ ]
A) An alkali metal B) An alkaline earth metal C) A lanthanide D) An actinide

8. The Hydrogen ion concentration of a solution is 0.0001 M. The nature of the solution is [ ]
A) Acidic B) Basic C) Neutral D) None of these

9. CO2 gas is cooled to form dry ice by sudden expansion. This is called [ ]
A) Einstein's effect B) Rutherford's effect C) Joule -Thomson's effect D) Bohr's effect [ ]

10. Potassium is a [ ]
A) Natural nutrient B) Primary nutrient C) Secondary nutrient D) Micro nutrient

II. Fill in the blanks:

11. Mass of a body is ------- anywhere in the universe.
12. Time of ascent is directly proportional to ------
13. Radio waves are produced by ------- in electronic circuits.
14. Magnetic field induction on the equatorial line is given by-----
15. ------- isotope is used in the determination of age of rocks.
17. The ------- period is incomplete.
18. The chemical formula of magnesite is ---------
19. The pH of NaCl is --------
20. The distance between two layers of Graphite is ---

III. Match the following:
I. Group A - Group B

21. Luminous flux [ ] A. Fermi
22. Electro motive force [ ] B. Hertz
23. Frequency [ ] C. Kilo watt hour
24. Electrical energy [ ] D. Volt
25. Radius of nucleus [ ] E. Lumen

II. Group A - Group B

26. Chromophore [ ] A. Na2CO3
27. Auxochrome [ ] B. NaOH
28. Soda ash [ ] C. C = S
29. Sodium hydroxide [ ] D. NaHCO3
30. Sodium bi carbonate [ ] E. - COOH

Answers: 1) D 2) B 3) D 4) A 5) B 6) C 7) D 8) A 9)C 10) B 11) Same 12) Initial velocity 13) Accelerating electrons 14) μ0M/4Πd3 15) Uranium 235 16) Frequency 17) 7th 18) MgCO3 19) 7 20) 3.35A0 21) E 22) D 23) B 24) C 25) A 26) C 27) E 28) A 29) B 30) D.