AP SSC 10th class General Science Model paper 2015-16 English Medium Set 2

AP SSC 10th class General Science Model paper 2015-16 English Medium Set 2

Section -I

Group – A
1. State any two differences between Convex and Concave mirrors.
2. Write the Len’s makers formula and explain the terms in it.
3. What do you mean by electric shock ? Explain how it take place.
4. By observing steel vessels and different images in them, Ramu, a third class student asked some questions to his elder sister Santha. What may be those questions?
Group – B
5. A mixture of Oxygen and Ethyne is burnt for welding. Can you tell why a mixture of Ethyne and air is not used ?
6. Which method do you suggest for extraction of high reactivity metals ? Why ?
7. Write any two uses and two properties of Covalent compounds.
8. Where do we use washing method in our daily life ? Give example. How do you correlate this example with enrichment of ore ?

SECTION – II

9. What is Humidity ?
10. Define Critical angle. .
11. What is the reason for using Tungsten as a filament in electric bulb ?
12. What is a Chemical bond ?
13. Name the simplest Hydrocarbon.
14. Mention two methods, which produce very pure metals.

SECTION – III

Group – A
15. Explain, why dogs pant during hot summer days using the concept of evaporation?
16. How can you verify that a current carrying wire produces a magnetic field with the help of an experiment ?
17. Write about your favourite scientist / physicist.
18. A house has four tube-lights, three fans and a television. Each tube-light draws 40 W. The fan draws 80 W and the television draws 100 W. On an average, all the tube- lights are kept on for 5 hours, all fans for 12 hours and the television for 6 hours everyday. Find the cost of electric energy used in 30 days at the rate of Rs. 3.00 per KWH.
Group – B
19. Write the balanced chemical reaction for the following and identify the type of reaction in each case.
A) Magnesium_(s) + Iodine_(g)——- > Magnesium iodide_(s)
B) Zinc_(s) + Hydrochloric acid_(aq)——- > Zinc chloride_(aq) + Hydrogen_(g)
20.Rainbow is an example for continuous spectrum. Explain.
21.What is meant by water of crystallisation of substance ? Describe an activity to show the water of crystallisation.
22. Comment on the position of Hydrogen in Periodic table.

SECTION – IV
23. Draw a neat diagram of an A.C. generator.
24. Draw a neat diagram of Reverberatory’ furnace and label its parts.

Answers

Section-I

Group – A
1. State any two differences between Convex and Concave mirrors.

2. Write the Len’s makers formula and explain the terms in it.
A. Lens maker’s formula :

f – focal length of the lens
R1, R₂ – Radii of curvature
n – Absolute refractive index
3. What do you mean by electric shock ? Explain how it take place.
A. When current of 0.0024A (or) P.D. 240v flow through the body, the functioning of organs inside the body gets disturbed. This disturbance inside the body is felt as “electric shock”.
This can be experienced when there is potential difference between one part of the body and another part. The electric shock is a combined effect of current and resistance of the body.
4. By observing steel vessels and different images in them, Ramu, a third class student asked some questions to his elder sister Santha. What may be those questions ?
A. Ramu may ask Santha the following (suggested) questions.
1). How these steel vessels form images ?
2) Are these steel vessels mirrors ?
3) Why the images are differ from vessel to vessel ?
4) Why one side they form large image and other side they form smaller image ?
5) As we move away from the vessels the size and shape of the image changed, why ?
6) Why the images are not so clear in the vessels ?

Group – B
5. A mixture of Oxygen and Ethyne is burnt for welding. Can you tell why a mixture of Ethyne and air is not used ?
A. 1) Ethyne when burnt in the presence of oxygen gives enough heat that can be used for welding.
2) Whereas if it is burnt in air which contains nitrogen, C0₂ and other inactive gaseous contents, sufficient oxygen is not available for burning ethyne to give the required heat.
6. Which method do you suggest for extraction of high reactivity metals ? Why ?
A. I suggest “Electrolysis of fused compounds” for the extraction of high reactivity metals.
Simple chemical reduction method like heating to reduce the ores of these metals are not feasible the temperature required for the reduction is too high and more expensive. Hence I suggest the method of “Electrolysis of Fused Compounds”.
7. Write any two uses and two properties of Covalent compounds.
A. Uses of Covalent Compounds :
1) Water which is covalent compound is of more use to us.
2) Sugar and different types of food materials extensively useful to us are covalent compounds.
3) 99% of our body consists of covalent compounds.
Properties of covalent compounds are :
1) Covalent compounds are liquids and gases at room temperature.
2) They have low melting point and boiling points due to weak vander val forces.
3) These are soluble in non polar solvents.
4) They are less or moderately reactive because of bond making and bond breaking involved in chemical reactions.
8. Where do we use washing method in our daily life ? Give example. How do you correlate this example with enrichment of ore ?
A. 1) We use washing method whth water to separate dust from Rice, dal, vegetables, fruits etc.
2) Ore particles are crushed and kept on a slopy surface. They are washed with controlled flow of w ater less dense dust impurities are carried away by water flow leaving more dense ore particles behind.

Section-II
9. What is Humidity ?
A. The amount of water vapour present in air is called humidity.
10. Define Critical angle.
A. The angle of incidence at which the light ray travelling front denser to rarer medium grazes the interface that angle of incidence is called critical angle.
11. What is the reason for using Tungsten as a filament in electric bulb ?
A. The reason for using tungsten as a filament in electric bulb is its higher values of
resistivity and melting point.
12. What is a Chemical bond ?
A. Chemical Bond :The force of attraction between any two atoms or a group of atoms that results a stable entity is called chemical bond.
13. Name the simplest Hydrocarbon.
A. Methane (or) CH₄
14. Mention two methods, which produce very pure metals.
A. Methods which produce very pure metals are :
1)Electrolytic Reduction. 2) Smelting

Section – III
Group – A
15. Explain, why dogs pant during hot summer days using the concept of evaporation?
A. 1) Dogs pant during hot summer days and get their body cooled. This cooling effect is due to evaporation. Evaporation is a surface phenomenon.
2) Temperature of a system falls during evaporation. During summer the temperature in the human body increases the temperature of the skin becomes higher and the water in the sweat glands starts evaporating. Since evaporation is a cooling process human body cools.
3) Dogs don’t have sweat glands. Their body is covered with hair. They have sweat- glands only in their feet.
4) So by panting the water on the tongue evaporates resulting in the cooling of the dogs body.
16. How can you verify that a current carrying wire produces a magnetic field with the help of an experiment ?
A. Experiment to verify that a current carrying wire produces a magnetic field.
(oersted experiment).

Description :
1. Take a thermocole sheet and fix two thin wooden sticks of height 1 cm which have small slit at the top of their ends.
2) Arrange a copper wire ‘24 gauge’ so that it passes through these slits and make a circuit.
3) This circuit consists of a 3 volt battery, key, copper wire in series.
4) Keep a magnetic compass below the wire as shown in the figure.
Procedure :
5) Bring a bar magnet close to the compass. The needle in the compass gets deflected due to the magnetic field of the bar magnet.
6) Remove the magnet, take it away from the circuit. You will not observe any deflection in the needle.
7) Now switch on the circuit and you will observe deflection in the needle of the compass.
8) Now we come to know that this is due to the magnetic field produced by the current carrying wire.
17. Write about your favourite scientist / physicist. .
A. My Favourite Scientist is C.V. Raman.
1)Sir C.V. Raman is an Indian Physicist.
2) His full name is Sir Chandrasekhara Venkata Raman.
3) He was born on 7 November 1888 at Thiruvanaikoli in Tamil Nadu State.
4) He worked in the field of light scattering earned him the 1930 Nobel Prize for physics.
5) He discovered that, when light traverses a transparent material, some of the deflected light changes in wavelength. This phenomenon is called Raman effect.
6) In 1954, he was honoured with the highest civilian award in India, the Bharat Ratna.
18. A house has four tube-lights, three fans and a television. Each tube-light draws 40 W. The fan draws 80 W and the television draws 100 W. On an average, all the tube-lights are kept on for 5 hours, all fans for 12 hours and the television for 6 hours everyday. Find the cost of electric energy used in 30 days at the rate of Rs. 3.00 per KWH.
A. The power used by
1) Four tube-lights of 40 W for 5 hours in 30 days
= 4x 40 x5x 30 = 2400 WH
2) Three fans of 80 W for 12 hours in 30 days
= 3 x 80 x 12 x 30 = 86400 WH
3) One television of 100 W for 6 hours in 30 days
= 1 x 100 x 6 x 30 = 18000 WH
4) Total electric energy used
= 24000 + 86400 + 18000 = 128400 WH W.H. converted into K.W.H. = 128.4 K.W.H. .
128400
1000
Cost of 1 unit = 3.00 Rs.
Amount to be paid for 128.4 units = 128.4 x 3 = 385.20 Rs

Group – B
19. Write the balanced chemical reaction for the following and identify the type of reaction in each case.
A) Magnesium_(s) + Iodine_(g)—— > Magnesium iodide_(s)
B) Zinc_(s) + Hydrochloric acid_(aq)—– > Zinc chloride_(aq) + Hydrogen_(g)
A. A) Mg + I₂——– > Mgl₂
This reaction is chemical combination.
B) B) Zn + 2HCl—— > ZnCl₂ + H₂
This reaction is chemical displacement.
20. Rainbow is an example for continuous spectrum. Explain.
A. Rainbow is an example for continuous spectrum.
1. Spectrum is a group of wavelengths.
2. When it rains in atmosphere more number of droplets are found. When sunlight incident on water droplet water droplet disperses light acting as a prisom.
3. Thus Rainbow is formed. This is called VIBGYOR.
4) The seven colours in VIBGYOR spreading continuously and the intensity of each colour varies from one point to the other. Hence rainbow is an example for continuous spectrum.
21. What is meant by water of crystallisation of substance ? Describe an activity to show the water of crystallisation.
A. The water molecules which forms part of the structure of a crystal are called water of crystallization.
Activity :
1) Observe the blue colour of the copper sulphate crystals. Take some copper sulphate crystals in a dry boiling tube and heat.
2) On heating the blue copper sulphate crystals tiny water droplets are noticed on sides of the test tube.
3) Now see the copper sulphate crystals turns white.
4) The reason is water present in crystals is evaporated.
5) When white copper sulphate crystals are moistened with water the blue colour of copper sulphate crystals is restored. The formula is CuS0₄ 5 H₂0.
6) By this activity it is proved that copper sulphate contains water of crystallization
22. Comment on the position of Hydrogen in Periodic table.
A. 1) Hydrogen is the element which has easy atomic structure than any other element.
2) Electron configuration of Hydrogen is Is¹. It has one proton in its nucleus and one electron in its Is orbital.
3) In periodic table the place of Hydrogen may be in I A or VII A groups.
4) Hydrogen properties resembles the properties of alkaline metals (I A elements) and Halogens (VII A elements).
5) As alkaline metals Hydrogen can loose one electron and accepts one electron as Halogens.
6) Basing on electronic configuration of hydrogen it is placed in I A.