# Properties of Matter Test 9

Paper: Physics      Class: 9                     Time Allowed:    One Hour                           Marks: 25

Q1. Circle the correct answer.  (10)

1.The density of a substance can be found with a help of :
a) Pascal’s law             b) Archimedes principle

c) hook’s law             d) principal of floatation
2.The molecules in gases are
a) closely packed               b) loosely packed

c) much far apart             d) none of these
3.The pressure of a gas in a container depends upon:
a) temperature               b) type of a gas

c) volume of container            d) shape of container
4.Mass per unit volume is called
a) pressure              b) density              c) weight        d) stress
5.The attractive forces between the molecules of solid are
a) less weak                  b) very weak             c) very strong            d) none of these
6.The S.I unit of young’s modulus is:
a) Nm            b) Nm-2             c) Nm2             d) all
7.What is the unit for strain?
a) no unit            b) Nm-1       c) Nm-2          d) none of these
8.Matter is composed of very small particles called
a) electrons             b) protons          c) molecules           d) neutrons
9.The liquid pressure will ______ with increase in depth
a) increase           b) decrease         c) not change            d) none
10.The S.I unit of density is
a) liter             b) kgm-2
c) kgm-2        d) Nm

Q2. Write short answers to these questions: (15)
1.Why does the atmospheric pressure vary with attitude?
2.What is upthurst force.؟
3.What do you mean by young’s modulus?
4.The density of air is 1.3 kg .. Find the mass of air in a room measuring 8mx5mx4m.
5.Define the term pressure write its formula and S1 unit.