Class – IX
Subject – Physics & Chemistry
Q.1 Why do we hear sound of approaching aero plane before it reaches us?
Q.2If an electric bulb of 60w lighted for 10 hrs. How much is the electric
energy consumed in joules?
Q.3 How many electrons are present in P3-?
Q.4 The speed of an arrow shooted from the bow is square root of its Kinetic
Energy. What is the mass of an arrow? (2x7)
Q.5 A girl vibrates her scale 20 cycles per minute. What is the time period
Q.6 What should be angle between force and displacement to get (a) Maximum
Work (b) Minimum Work
Q.7 What is the meaning of “ECHOLOCATION” give example?
Q.8 State Atomicity and polyatomic ion in one sentence with example?
Q.9 An element X form its oxide X2O3 what will be formula of its phosphate?
Q.10 How many atoms are present in 0.024 g of Ca atom?
Q.11 If a source of sound produces 10 crests and 10 troughs in 2 sec. then
calculate the frequency of the wave. (3x7)
Q.12 Explain the transformation of energy in hydroelectric power plant?
Q.13 A bag of wheat weighs 50 kg, find the height to which it should be
raised so that Potential Energy is 5000 J (g: 10ms-2)?
Q.14 Tortoise A argue with argue with tortoise B according to A we weigh lens
in water than Air but B oppose it. Who is correct A or B and which principal use
by correct one?
Q.15 Which one has greater mass 0.1 mole of CO2 or 0.2 mole of NH3?
Q.16 An element X of electronic configuration 2,4 react with Y of which ion
is Y2- form compound which is responsible for pollution of environment. Identify
X,Y, compound formed and calculate the molecular mass of compound.
Q.17 How 20 10Z and 22 10Z related to each other and why ? If abundance of
2010Z and 22 10Z is 90% & 10% respectively then calculate the average atomic
mass of Z?(5x2)
Q.18 (a)Calculate the power of pump which raises 50 kg of water through a
height of 25 m in 5 sec. (b)Derive Kinetic energy formula, using the formula
find the ratio of KE of two objects of masses4 m, m with velocities v,2v
respectively.(c) According to given diagram if 20 such ripples produced per
second then calculate (i) frequency (ii) wave length (iii) wave velocity.
Q.19 (i)Discuss the Rutherford’s model of an Atom with keeping following
points in mind- (a) Diagram (b) Observations (c) Conclusions.
Q. 20 Write also major drawback of Rutherford’s model of an atom and how the
drawbacks was rectified? The mass of an atom X is 2.0x10-23 g Calculate the
approx atomic mass of X and what could be X.
Contributed By: Jsunil