# Properties of Matter Test 18

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

Q1. Circle the correct answer.  (10)

1.The S.I unit of density is
a) liter          b) kgm-2
c) kgm-3      d) Nm
2.What is the unit for strain?
a) no unit          b) Nm-1      c) Nm-2         d) none of these
3.Mass per unit volume is called
a) pressure          b) density        c) weight        d) stress
4.The molecules in gases are
a) closely packed          b) loosely packed

c) much far apart         d) none of these
5.The liquid pressure will ______ with increase in depth
a) increase            b) decrease          c) not change           d) none
6.The S.I unit of young’s modulus is:
a) Nm           b)             c) Nm2         d) all
7.Matter is composed of very small particles called
a) electrons             b) protons             c) molecules              d) neutrons
8.The attractive forces between the molecules of solid are
a) less weak           b) very weak          c) very strong              d) none of these
9.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
10.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
Q2. Write short answers to these questions: (15)
1.What do you mean by young’s modulus?
2.The density of air is 1.3 kg .. Find the mass of air in a room measuring 8mx5mx4m.
3.What is upthurst force.؟
4.Why does the atmospheric pressure vary with attitude?
5.Define the term pressure write its formula and S1 unit.