std 9th Science I whole portion 2020

Q 1 A) Choose the correct alternative and rewrite the correct statement. ( 1 mark each )

1.The force necessary to cause an acceleration of 1m/second square in an object of mass 1kg is called_______.
(a) 1 dyne     (b) 1m/s    (c) 1 newton   (d) 1cm/s

2.The work done on an object does not deppend on ________
(a) displacement   (b) applied force   (c) initial velocity of the object   (d) the angle between force and displacement.

3.In order to measure the  electric current flowing through a circuit , we connect _______ with the circuit.

4.The unit dalton is used to express _______
(a) atomic mass  (b) atomic number   (c) atomic radius  (d) mass number

5. The solution turns blue litmus paper red, its pH is likely to be _________
(a) 7              (b) 4            (c) 14          ( d) 9

Q 1. B) State whether the following statement are true or false. If false rewrite the correct statement
Unit of power is Joule. (1 M )

C) Complete the following  (1 M )
K.E = _____________

D) Write the molecular formula of Calcium Carbonate   (1 M )
E) Find odd man out and justify   (1 M )
Ammonium Chloride, Sodium Chloride, Potassium Nitrate, Sodium Sulphate

F) Give two example of basic radicals  (1 M )

Q 2 A) Give Scientific reasons (2 Marks each )
1 It is easier to stop tennis ball as compared to Cricket ball when both are travelling with same velocity.
2. The valency of Magnesium is 2.
3. The intensity of reverberation is higher in a closed and empty house

Q 2 B) Answer the following  (2 Marks each )
1. Write the harmful effects of artificial dye.
2. What are the uses of Ultrasonic sound.
3. An object 4 c m in height is placed at a distance of 36 cm from a concave mirror. The image is formed 18 cm in front of the mirror find the height of the image.
4. If an object has 0 momentum, does it have kinetic energy? explain your answer
5. Differentiate between Voltmeter    and Ammeter ?

 Q 3 Answer the following (3 Marks each )
1. Write the uses of radioactive substances in medical science.
2. Give the properties of graphite
3. What are the rules for drawing ray diagrams for the formation of image by spherical mirror ?
4. Two resistors having  resistances of 16 Ohm and 14 Ohm are connected in series if a potential difference of 18 V is applied across them, calculate the current flowing though the circuit and potential difference across each individual resistor.
5.A motor boat starts from rest and moves with uniform acceleration. If it a attains the velocity of 15 m / sec  in 5 sec.  Calculate the acceleration and distance traveled in that time.
6. Explain what is meant by electrolysis of water. Write the electrode reactions and explain them.
7. Draw the symbols for components of an electric circuit and write their uses
a) crossing wires         b) battery       c) close tap key and plug key
8. How will the compound CaO be formed from their elements ?

Q 4 Answer in detail (5 Marks each )
1. Derive an expression for resistances connected in parallel
2. Prove that the kinetic energy of a freely falling object on reaching the ground is nothing but the transformation of its initial potential energy

Comments

Popular posts from this blog

हिंदी कक्षा सातवी प्रथम सत्र परीक्षा

Std. 10 Ch. 8 Economy and Occupations Practice paper of Geography