S.I.W.S. Science Preliminary Examination 2016

Preliminary Examination  - 2016

Science and Technology (Part I) (72)

Q1. A. Write whether the following statements are True or False. (2)

1. SO₃ , O₃ , Ketones are secondary pollutants. 

2. The S.I. unit of charge is volt.

B. Match the following. (3)

Group A	Group B
1. Glass	a. Nickel
2. Catalyst	b. 50 Hz
3. Frequency of AC	Non biodegradable
	0 Hz

C. Rewrite the following statements by selecting the correct options. 5

1. Alnico is an alloy of ______________

a. Al, Ni, & C.

b. Al, Ni, & Co.

c. Al, N & C.

d. Al, N & Co.

2. _____________ is a natural indicator.

a. Turmeric

b. Phenolphthalein

c. Methyl orange

d. Eosin

3. If three resistors of 5 Ω , 6 Ω , 8Ω are connected in series. Then the effective resistance is _____________.

a. 24Ω

b. 240Ω

c. 7Ω

d. 19Ω

4. The image formed by convex mirror is always __________.

a. real and magnified.

b. virtual & diminished.

c. real and diminished

d. virtual & magnified.

5. Acids turn blue litmus paper _________.

a. red

b. remains - blue.

c. yellow

d. colourless.

Q2. A. Solve the following questions. (Any 5)  (10)

1. Give reasons : - Edible oil is not allowed to stand for a long time in an iron or in tin container.

2. If a bulb of 60 w is connected across a source of 230V. Find the current drawn by it.

3. Draw well labelled ray diagram for image formation by convex lens when object is between focus F1 & optical centre 'O'.

4. Write short note on "Dispersion of light."

5. State four characteristics of Newland's periodic table.

6. Write any four application of concave mirror.

Q3. Answer the following questions (Any 5)  (15)

1. State: Right hand thumb rule with proper diagram.

2. When you add Potassium Chromate (K₂CrO₄) to Barium Sulphate (BaSO₄) Solution .

3. What are the adverse effects of sound pollution on human body?

4. Name the following:

a. An alkali metal in periodic table.

b. A halogen element in the period three.

c. An inert gas in period one.

5. Methyl orange is used as an indicator. It shows colour changes in acid, base and neutral substance. Tabulate your results as follows in the table.

Indicator	Solution	Colour Change	Inference
Methyl Orange	a) b) c)	Yellow No Change	Basic

6. Give reasons: Stars twinkle at night.

Q4. Answer the following questions. (Any 1) (5)

1. Write the construction, principle and working of "electric motor with well labelled diagram."

2. Complete the following flow chart.