9th Class Physics Past Paper 2021 Evening
Note: Physics 2nd Time Paper of 9th Class.
Group-II (Subjective) 40 Marks
Part– I
Q.2 Write short answers to any FIVE (5) questions:
(i) Write any four names of base quantities.
(ii) What do you mean by scientific notation? Give an example.
(iii) What is meant by vernier constant?
(iv) Differentiate between scalars and vectors.
(v) Define acceleration and write its formula.
(vi) Describe a vector by graphical method.
(vii) Define force and write its unit.
(viii) What is meant by coefficient of friction? Also write its symbol.
Q.3 Write short answers to any FIVE (5) questions:
(i) What is meant by resultant force?
(ii) Define moment and state the principle of moments.
(iii) What are artificial satellites?
(iv) What is meant by force of gravitation?
(v) What are natural satellites?
(vi) Define kinetic energy and potential energy.
(vii) How can you find the efficiency of a system?
Q.4 Write short answers to any FIVE (5) questions:
(i) Define density and give the density of water.
(ii) What is elasticity?
(iii) Define stress and give its unit.
(iv) Define internal energy.
(v) What is meant by latent heat of vaporization?
(vi) What are the three ways of transfer of heat? Write their names.
(vii) Define thermal conductivity.
(viii) Write two uses of convection currents.
PART-II
Note: Attempt any TWO questions.
Q.5
(a) State and explain the law of conservation of momentum.
(b) A train starts from rest with an acceleration of 0.5 m/s⁻2. Find its speed in km/h⁻1, when it has moved through 100 m.
Q.6
(a) Define equilibrium. State and explain the first condition of equilibrium.
(b) A motorboat moves at a steady speed of 4 m/s⁻1. The water resistance acting on it is 4000 N. Calculate the power of its engine.
Q.7
(a) State Pascal’s law and explain the hydraulic press.
(b) Calculate the increase in the length of an aluminum bar 2 m long when heated from 0°C to 20°C. The thermal coefficient of linear expansion of aluminum is 2.5 × 10⁻5 K-1.